this low, and numerous schemes to this effect were propounded, but now it has become generally recognized that a high pitched engine will travel as steadily and more safely round a curve–given a good road–than a low pitched one; and thus while in 1850 the average height of the center line of boilers varied between 5 ft. 3 in. and 6 ft. 3 in., now in the latest designs it lies between 7 ft. and 7 ft. 6 in. Single frames are very generally adopted, but double frames and outside bearings to the leading and trailing wheels, as in the Great Western engines, give great steadiness in running, and this class has also double bearings to the driving wheels, thus entailing greater security in case of the facture of a crank axle. The general adoption of cabs on the foot-plate for the men is another improvement of late introduction, although at first not universally appreciated by those for whose comfort it was designed–“I felt as if I was in my coffin,” said an old driver when asked how he liked the new shelter. Mild steel fire-boxes, which have been employed in America, are not in favor here, copper being universally used; they have been tried on the Caledonian, Great Southern and Western, North London, and North-Western, and were found not to succeed. Brake blocks of cast iron have now generally superseded wood; steel is being more and more used, especially on the North Western. There is less use of brasswork for domes and fittings, although it is claimed for brass that it looks brighter and can easily be kept clean. There is greater simplicity of design generally, and the universal substitution of coal as coke for fuel, with its consequent economy; and last, but not least, the adoption of standard types of engines, are among the changes which have taken place in locomotive practice during the past quarter of a century.
[Illustration: FIG. 8.–LONDON, CHATHAM, & DOVER RAILWAY.]
[Illustration: FIG. 9.–GREAT EASTERN RAILWAY.]
[Illustration: FIG. 10.–MANCHESTER, SHEFFIELD, AND LINCOLNSHIRE RAILWAY.]
Having now reviewed, as far as the limits of this paper will allow, the locomotive practice of the present day, the author would in conclusion draw attention to what may possibly be one course of locomotive development in the future. Time is money, and it may be in the coming years that a demand will arise for faster means of transit than that which we possess at present. How can we meet it? With our railways laid out with the curves and gradients existing, and with our national gauge, and our present type of locomotive, no great advance in speed is very probable; the mean speed of express trains is about fifty miles an hour, and to take an average train of 200 tons weight at this speed over a level line requires between 650 and 700 effective horse-power, within the compass of the best engines of the present day. But if instead of fifty miles an hour seventy is required, an entirely different state of things obtains. Taking a train of 100 tons, with engine and tender weighing 75 tons, or 175 tons gross, the first question to determine will be the train resistance, and with reference to this we much want careful experiments on the subject, like those which Sir Daniel Gooch made in 1848, on the Bristol and Exeter Railway, which are even now the standard authority; the general use of oil axle-boxes and long bogie coaches, irrespective of other improvements, would render this course desirable. With regard to the former, they appear to run with less friction, but are heavier to start, oil boxes in some experiments made on the South-Western Railway giving a resistance of 2.5 lb. per ton, while grease boxes ranged from 6 lb. to 9 lb. per ton. Again, the long and heavy bogie Pullman and other coaches have the reputation among drivers, rightly or wrongly, of being hard to pull. The resistance of an express train on the Great Western Railway at seventy-five miles an hour was 42 lb. per ton, and taking 40 lb. per ton for seventy miles an hour would give a total resistance on the level of 7,000 lb., corresponding to 1,400 horse-power–about double the average duty of an express engine of the present day. The weight on the driving wheels required would be 183/4 tons, allowing one-sixth for adhesion, about the same as that on the driving axle of the Bristol and Exeter old bogie engines. Allowing 21/2 lb. of coal per horse-power per hour would give a total combustion of 3,500 lb. per hour and to burn this even at the maximum economic rate of 85 lb. per square foot of grate per hour would require a grate area of 41 square feet, and about 2,800 square feet of heating surface. Unless a most exceptional construction combined with small wheels is adopted, it appears almost impossible to get this amount on the ordinary gauge. It is true the Wootten locomotives on the Philadelphia and Reading Railway have fire-boxes with a grate area of as much as 76 square feet, but these boxes extend clean over the wheels, and the heating surface in the tubes is only 982 square feet; but although these engines run at a speed of forty-two miles an hour, they are hardly the type to be adopted for such a service as is being considered. On the broad gauge, however, such an engine could easily be designed on the lines now recognized as being essential for express engines without introducing any exceptional construction, and there appears but little doubt that were Brunei’s magnificent gauge the national one, competition would have introduced a higher rate of speed between London and our great towns than that which obtains at present.
The whole question of the future introduction of trunk lines, exclusively for fast passenger traffic, is fraught with the highest interest, but it would be foreign to the subject matter of this paper to enter more fully on it, the author merely desiring to state his opinion that if the future trade and wealth of our country require their construction, and if a very high rate of speed much above our present is to be attained, their gauge will have to be seriously considered and settled, not by the reasons which caused the adoption of the present gauge, but by the power required to carry on the traffic–in fact, to adapt the rail to the engine, and not, as at present, the engine to the rail. High speed requires great power, and great power can only be obtained by ample fire-grate area, which for a steady running engine means a broad gauge. The Gauge Commissioners of 1846 in their report esteemed the importance of the highest speed on express trains for the accommodation of a comparatively small number of persons, however desirable that may be to them, as of far less moment than affording increased convenience to the general commercial traffic of the country. The commercial traffic of England has grown and prospered under our present system, and if its ever increasing importance demands high speed passenger lines, we may rest assured that the ingenuity of man, to which it is impossible to assign limits, will satisfactorily solve the problem.
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SCREW STEAM COLLIER FROSTBURG.
[Illustration: NEW STEAM COLLIER.]
Our diagram shows the screw steam collier Frostburg, built by Henry H. Gorringe (the American Shipbuilding Co.), Philadelphia, Pa. Length, 210 ft. Beam, 33 ft. Depth, 17 ft, Register tonnage, 533. Carrying capacity on 14ft., 1,100 tons, and 100 tons coal in bunker. Cubical contents of cargo space, 55,168 cub. ft. Carrying capacity on 16 feet draught, 1,440 tons. Engines, compound surface condensing. High pressure 26 in. diameter, low pressure 48 in. diameter, stroke 36 in. Two boilers, each 13 ft. diameter. 10 ft. long, and one auxiliary 5 ft. diameter and 10 ft. high. 100 lb. working pressure. Sea speed with full cargo, 11 knots.
* * * * *
A thirteen year old girl, who is perfect in other ways, but who has simply little blue spots that puff out slightly where her eyes should be, is said to be living at Amherst, Portage County, Wisconsin.
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DESTRUCTION OF THE TARDES VIADUCT.
The railroad from Montlucon to Eygurande, which is being constructed by the state engineers, crosses the valley of the Tardes in the environs of Evaux (Creuse).
At the spot selected for the establishment of the viaduct the gauge is deep and steep. The line passes at 300 feet above the river, and the total length of the metallic superstructure had to be 822 feet. To support this there was built upon the right bank a pier 158 feet in height, and, upon the left, another one of 196 feet. The superstructure had been completed, and a portion of it had already been swung into position, when a violent, gale occurred and blew it to the bottom of the gorge. At the time of the accident the superstructure projected 174 feet beyond the pier on the right bank, and had to advance but 121 feet to reach the 33 foot scaffolding that had been established upon the other pier.
It blows often and violently in this region. For example, a gale on the 20th of February, 1879, caused great damage, and, among other things, blew the rear cars of a hay train from the top of the Louvoux viaduct to the Bouble.
The superstructure of the Tardes viaduct had already withstood the tempest of the 23d and the 24th of January, 1884, and neither any alteration in its direction nor any change in the parts that held it upon the pile could be perceived. But on the night of January 26-27 the storm doubled in violence, and the work was precipitated into the ravine. No one was witness of the fall, and the noise was perceived only by the occupants of the mill located below the viaduct.
The workmen of the enterprise, who lived about 325 feet above this mill and about 650 feet from the south abutment, heard nothing of it, the wind having carried the noise in an opposite direction. It was not until morning that they learned of the destruction of their work and the extent of the disaster.
One hundred and sixty-nine feet of the superstructure, weighing 450 tons, had been precipitated from a height of nearly 200 feet and been broken up on the rock at 45 feet from the axis of the pier. The breakage had occurred upon the abutment, and the part 195 feet in length that remained in position in the cutting was strongly wedged between walls of rock, which had kept this portion in place and prevented its following the other into the ravine.
Upon the pier there remained a few broken pieces and a portion of the apparatus used in swinging the superstructure into place.
Below, in the debris of the superstructure, the up-stream girder lay upon the down-stream one. The annexed engraving shows the state of things after the disaster.
Several opinions have been expressed in regard to the cause of the fall. According to one of these, the superstructure was suddenly wrenched from its bearings upon the pier, and was horizontally displaced by an impulse such that, when it touched the masonry, its up-stream girder struck the center of the pier, upon which it divided, while the down-stream one was already in space. The fall would have afterward continued without the superstructure meeting the face of the pier.
[Illustration: DESTRUCTION OF THE TARDES VIADUCT.]
Upon taking as a basis the horizontal displacement of the superstructure, which was 45 meters to the right of the pier, and upon combining the horizontal stress that produced it with that of the loads, the stress exerted upon the body may he deduced. But this hypothesis seems to us scarcely tenable, especially by reason of the great stress that it would have taken to lift the superstructure. On another hand, it was possible for the latter to slide over one edge of the pier, and this explains the horizontal distance of 45 feet by which its center of gravity was displaced. It is probable, moreover, that the superstructure, before going over, moved laterally upon its temporary supports.
The girders were, in fact, resting upon rollers, and the roller apparatus themselves were renting upon wedges, and there was no anchorage to prevent a transverse sliding.
Under the prolonged thrust of a very high wind, the superstructure, by reason of its considerable projection, must have begun to swing like a pendulum. These oscillations acquired sufficient amplitude to cause the superstructure to gradually move upon its rollers until the latter no longer bore beneath the webs. The flanges therefore finally bent upward where they rested upon the rollers, through the action of the weight which they had to support, and the entire superstructure slid off into space.
An examination of the bent pieces seems to give great value to this hypothesis.–_Le Genie Civil_.
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JOY’S REVERSING AND EXPANSION VALVE GEAR.
[Footnote: A paper read before the Mechanical Section of the British Association, at Montreal, August, 1884.]
Four years ago, in August, 1880, a paper was read on this subject before the Annual Summer Meeting of the Mechanical Engineers’ Society of Great Britain, then held in Barrow-in-Furness, describing this valve motion and its functions, which was then comparatively new. It was, however, illustrated by its application to a large express goods (freight) engine, built by the London and North-Western Railway Company (England) specially to test the advantages and the endurance of the gear. This engine had cylinders of 18 inches in diameter and 24 inch stroke, and six wheels coupled 5 feet 1 inch diameter, and was designed by Mr. Webb, the Company’s chief engineer, for their heavy fast goods traffic on the main line. The engine has been running this class of traffic ever since. In January, 1884, it was passed through the repair shops for a general overhauling, when it was found that the valve motion was in such good condition as to be put back on the engine without any repairs.
The main object of this present paper is to deal with the advantages of the valve gear and its application to various classes of engines both on land and at sea, and with the results of such applications, rather than treating it as a novelty, to give an exhaustive description of its construction and functions, which was done in the paper above referred to. A very short description of its action and main features will, however, be necessary to the completeness of the paper, and as a basis from which the improved results to be recorded should necessarily be shown to spring.
The essential feature of this valve gear is that movement for the valve is produced by a combination of two motions at right angles to each other; and by the various proportions in which these are combined, and by the positions in which the moving parts are set with regard to each other, it gives both the reversal of motion and the various degrees of expansion required. Eccentrics are entirely dispensed with and the time-honored link gear abandoned, the motion is taken direct from the connecting rod, and by utilizing independently the backward and forward action of the rod, due to the reciprocation of the piston, and combining this with the vibrating action of the rod, a movement results which is suitable to work the valves of engines, allowing the use of any proportions of lap and lead desired, and giving an almost mathematically correct “cut-off” for both sides of the piston and for all points of expansion intermediately, as well as a much quicker action at the points of “cut-off” and “release” than is given by a link gear.
The machinery for accomplishing this is both less costly and less complicated than the ordinary link motion, and is shown in elevation on cut, which is a view of the complete motion as on the first London and North-Western locomotive. Here E is the main valve lever, pinned at D to a link, B, one end of which is fastened to the connecting rod at A, and the other end maintained in about the vertical by the radius rod, C, which is fixed at the point, C. The center or fulcrum, F, of the lever, E, partaking of the vibrating movement of the connecting rod at the point, A, is carried in a curved slide, J, the radius of which is equal to the length of the link, G, and the center of which is fixed to be concentric with the fulcrum, F, of the lever when the piston is at either extreme end of its stroke. From the upper end of the lever, E, the motion is carried direct to the valve by the rod, G. It will be evident thus that by one revolution of the crank the lower end of the lever, E, will have imparted to it two different movements, one along the longer axis of the ellipse, traveled by the point, A, and one through its minor axis up and down, these movements differing as to time, and corresponding with the part of the movement of the valve required for lap and lead, and that part constituting the port opening for admission of steam.
[Illustration: JOY’S REVERSING AND EXPANDING VALVE GEAR.]
The former of these is constant and unalterable, the latter is controllable by the angle at which the curved slide, J, may be set with the vertical.
It will further be evident that if the lever, E, were pinned direct to the connecting rod at the point, A, which passes through a practically true ellipse, it would vibrate its fulcrum, F, unequally on either side of the center of the curved slide, J, by the amount of the versed sine of the arc of the lever, E, from F D; it is to correct this error that the lever, E, is pinned at the point, D, to a parallel motion formed by the parts, B and C. The point, D, performing a figure which is equal to an ellipse, with the error to be eliminated added, so neutralizing its effect on the motion of the fulcrum, F.
The “lap” and “lead” are opened by the action of the valve lever acting as a lever, and the port opening is given by the incline of the curved slide in which the center of that lever slides, and the amount of this opening depends upon the angle given to that incline. When these two actions are in unison, the motion of the valve is very rapid, and this occurs when the steam is being admitted. Then follows a period of opposition of these motions, during which time the valve pauses momentarily, this corresponding to the time when the port is fully open. Further periods of unison follow, at which time the sharp “cut-off” is obtained.
The “compression” resulting with this gear is also reduced to a minimum, owing to the peculiar movement given to the valves (_i. e._, the series of accelerations and retardations referred to), as, while the “lead” is obtained later and quicker, the port is also shut for “compression” later and quicker, doing away with the necessity for a special expansion valve, with its complicated and expensive machinery, and allowing the main valve to be used for expansion, as the “compression” is not of an injurious amount, even with a “cut-off” reduced to 15 per cent., or about 1/6 of the stroke.
Thus, so far as the distribution of the steam and its treatment in the cylinder is concerned, a marked advantage is shown in favor of this valve gear. But next in its favor, as before said, is that the above advantages are not gained at the cost of added complication of parts or increased cost of machinery, but the reverse, as this gear can be built at a less cost than link gear, varying according to the circumstances, but reaching as high as a saving of 25 per cent., or, if it be compared with a link gear supplemented by the usual special expansion valve and gear as employed on marine engines, then the total saving is fully 50 per cent., and an equally good result is obtained as to the distribution and subsequent treatment of the steam.
After accuracy of result and reduction in cost may rank saving room and the advantages arising therefrom (though for steamships perhaps this should have come first). Taking locomotives of the inside cylinder type, which is the general form in use in England and the continent of Europe, by clearing away the eccentrics and valves from the middle of the engine, much larger cylinders may be introduced and a higher rate of expansion employed, and this is being done. Also room is left for increasing the length and wearing surfaces of all the main bearings with even less crowding than is now the case with engines with the smaller cylinders.
But this advantage of saving room comes much more prominently forward in marine engines, especially in war ships, where every inch of room saved is valuable; and in the new type of triple-cylinder engines now coming so much into vogue in the mercantile marine, whether those engines be only the ordinary three-cylinder engines with double expansion, or the newer, triple expansion engine, expanding the steam consecutively through three cylinders–the form of marine engine which promises to come into use wherever high-class work and economy are required. On this system, by placing all the valve chests in front of the cylinders instead of between them, or in a line with them, sufficient room is saved to get the new-type three-cylinder engine into the space occupied by the old form of two-cylinder engine.
Besides these prominent advantages there are others which, though of minor importance, are still necessary to the practical and permanent success of any new mechanical arrangement, such as the accessibility of all the working parts while in motion, for examination and oiling; the ease with which any part or the whole can be stripped and cleaned, or pinned up out of the way in case of break down or accident, or got at and dismantled for ordinary repair; the ease with which the whole may be handled, started, reversed, or set at any point of expansion–all these being recommendations to enlist the care and attention of the engineers in charge by lightening their duties and rendering the engines easy to work.
With those advantages it is perhaps not surprising that this valve gear has been very considerably adopted for many classes of steam engines, especially where a high result has been required, with economy of space, and a minimum of complication.
Having crucially tested the original engine on the London and North-Western Railway, Mr. Webb proceeded to build others similar, and on his bringing out his Compound Express Engine–notably the most advanced step in locomotive design of the present day–he adopted this valve gear throughout. There are now a number of these engines running some of the fastest trains on the London and North-Western Railway, with the most satisfactory results.
Following these, others of the leading railways took up the system, and prominently among these Mr. Worsdell, of the Great Eastern Railway, built a number of large express engines for his fast and heavy traffic, and is now building a number of others similar as to the valve gear for his suburban traffic, which is specially heavy. Also the Lancashire and Yorkshire and the Midland and others of the chief railways are employing the system specially for large express engines; the Midland engines having cylinders of 19 inches diameter by 26 inches stroke, and four coupled wheels of 7 feet diameter. A number of the above-named engines have run large mileages, in many cases already exceeding 100,000 miles per engine. For other countries also a number of locomotive engines have been built or contracted for–both of inside and outside cylinder types–making a total of nearly 800 locomotives built and building, many of them being of special design and large size, up to 20 inches and 21 inches diameter of cylinder.
In all these the absence of wire-drawing may be specially noted by the full line at the top of the diagram, showing the admission of steam–this fullness arising from the rapid and full opening of the port for admission.
Passing now to the other great type of engines, those covered under the general designation of marine engines, this gear has been applied to nearly 40,000 H.P. indicated, built and building, and to all classes and sizes, from the launch engine with cylinders 8 inches by 9 inches, running at 600 to 700 revolutions per minute, up to engines for the largest class of war ships, such as her Britannic Majesty’s steel cruiser Amphion, of 5,000 H.P., with cylinders in duplicate of 46 inches and 86 inches diameter, and 3 feet 3 inches stroke, running 100 revolutions per minute. An examination of the indicator diagrams taken from these engines shows that no wire-drawing takes place, and that, though the expansion is carried to a point beyond the ordinary requirements, the compression is but slightly increased. In all the diagrams taken from this valve motion there is seen the clear, full upper line showing an abundant admission of steam without any wire-drawing, and also the distinctly marked points where “cut-off” or “suppression” and where “release” takes place, showing the rapid action of the valves at those points.
It is well known to engineers that to obtain the maximum advantage out of compounding, it is necessary to cut off in the low pressure cylinder at a point corresponding to the relation between the low and the high, and that point should be unaltered, whereas the point of cut-off in the high may at the same time be varied to suit the work to be done.
In an ordinary link motion engine (where both links are connected to the same weigh shaft), when linking up the high pressure cylinder to cut-off short, the same change is necessarily made in the low. By the use of the Joy gear, cut-off valves may be fitted to both cylinders, that for the low pressure being fixed at the constant position required by the proportion of the cylinders, while that on the high is adjustable; of course, in this case, the position of the quadrants must be only changed for reversing. In arranging the independent cut-off on the Joy gear, it is only necessary to increase the length of the vibrating link beyond the point of attachment for the main valve spindle connection to obtain a point from which motion may be taken to actuate the cut-off valve; even then the cost of the Joy gear for both cylinders is but little more than for a single set of link gear.
This arrangement gives an absolutely perfect distribution of steam for compounding, also equalizes the power developed by both cylinders, and is far more simple and inexpensive than any other gear in existence.
* * * * *
THE STEAM BELL.
[Illustration: FIG. 1.]
[Illustration: FIG. 2.]
The secondary railways in rural districts in Austria having no gates or bars at the level crossings, or guards at such points, but being open like tramways, special precautions are required to avoid accidents, and the public has to be warned of the approach of the train from a sufficient distance. This is done by ringing bells preferably to sounding whistles, as these are more likely to startle horses. The steam bell shown by our illustrations has been adopted for this purpose on the Austrian lines, and is a simple contrivance. It consists of a cylindrical chamber, a, ending in a narrower tube, c, which forms the seating for a flap valve, d, to which the hammer or clapper, e, is fixed. Steam is admitted through a small pipe, b, at the bottom, and after a certain interval attains sufficient pressure to lift the valve. The opening being large compared with the pipe, b, steam escapes more rapidly than it arrives through the small orifice; the pressure falls, and the valve drops down and causes the hammer to strike a bell surrounding the cylinder. The valve is provided with an internal collar as shown, so that it has to rise for the width of this before the steam is let out, and thus determines the swing of the clapper and the force of the blow. To intensify the latter and multiply the number of blows, the clapper spring is prolonged over the fulcrum and bent back so as to form a spring, which is tightened by the lifting of the flap, and sends the clapper down on the bell with increased force. The hinge of the flap does not require any lubrication besides what it gets through the steam. The bell is fixed upon the roof of the driver’s cab, so that the steam does not interfere with his lookout, and fastened by three bolts or screws. The diameter of the steam-pipe is from 1/4 to 1/2 inch according to the size of the bell, and the distance of the clapper from the bell is a little less than the diameter of the corresponding cock. The steam cock is perforated as shown by the illustration to drain the pipe when shut, and a small hole, b, in the bell cylinder drains the latter. The steam-pipe is made with a bend as usual, to allow for contraction and expansion. The number of blows given varies according to the steam pressure, and the opening of the steam cock; it is
With 90 lb. pressure, and cock 1/2 open, 170 blows per min. ” ” ” ” 1/3 ” 136 “
105 ” ” ” 1/2 ” 240 ” ” ” ” ” 1/3 ” 156 “
” ” ” ” 1/5 ” 136 “
120 ” ” ” 1/3 ” 228 ” 135 ” ” ” 1/5 ” 200 “
To start the bell, the cock is opened full, and afterward partly closed. The blows follow in such rapid succession that a kind of uniform sound with louder intervals is produced, but not of the same shrill character as by a steam whistle. The same kind of bell is used on the shunting engines in goods yards, where roadways have to be crossed on which lurries and handtrucks circulate, and the results as far as prevention of accidents is concerned are stated to be very satisfactory.
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LIEUT. GREELY BEFORE THE BRITISH ASSOCIATION.
Lieuts. Greely and Ray were received with distinguished honors at the meeting of the British Association in Montreal. A complimentary luncheon was tendered him by the members of the British Association for the Advancement of Science, at the Windsor Hotel. General Sir Henry Lefroy presided. In response to the toast “Our Distinguished Guests,” coupling the names of Lieuts. Greely and Ray and Mrs. Greely, Lieut. Greely said:
“_Mr. President, Ladies and Gentlemen_: I need scarcely say that this flattering reception from representative men of one of England’s most distinguished societies touches deeply my feelings as a soldier and as a man. It is not alone that you represent the science and learning of England and the world, but that you are all countrymen of those daring seamen and explorers whose names and whose deeds have become household words throughout the world. Hudson, Baffin, Cook, Nelson, Parry, Franklin, and a score of others among the dead; McClintock, Nares, and Markham, and last, but not least, the man whose name was oftenest on our lips when praying for relief during the past terrible winter–Bedford Pim. What those men have done the whole world knows. That you should deem aught that I have done worthy to placed with the deeds of those illustrious men must always be a source of pride to me. For three centuries England maintained against the world the honors of the farthest north. Step by step every advance was made by Englishmen. Now England’s grandest colony presses to the front; but none the less is the honor England’s, for at the price of her sons’ lives and by their toil the path was cleared. But for Beaumont’s dauntless pluck and indomitable energy in 1876, Lockwood would never had made his great northing in 1882. I have during a quarter of a century’s service, as becomes a soldier, been jealous of my honor. I have striven to maintain it in the field, fighting and bleeding for my country, and at my desk studying and discussing scientific data; in the Arctic Circle, when pursuing scientific and geographical work, or later, when stranded by adverse fate, and starving and freezing upon the barren coast. This marked and public testimonial of your approval cannot fail to make me doubly jealous of it in days to come.”
Lieut. Ray followed, returning thanks in his own behalf.
After other speeches Sir Henry Lefroy presented Lieutenant Greely with the following informal address:
“Montreal, Sept. 2, 1884.
“The undersigned, on behalf of many warm friends and admirers, and as representing various professional and scientific pursuits, desire to express to you their appreciation of the courage and devotion which has characterized your conduct during the trying circumstances of your late Arctic service. We trust that your health may soon be restored, and that you may long be spared to tender, as during your past distinguished career, those valuable and distinguished services to your great country which have already placed you among the foremost of scientific explorers of the age.
“Yours faithfully, Rayleigh, President.”
In introducing Lieut. Greely, Sir Henry Lefroy, referring to the persistence of purpose shown by his party in bringing back the pendulum apparatus, remarked that there was nothing nobler in the annals of scientific heroism than the determination of these hungry men to drag the cumbersome box along their weary way.
It was fully two minutes after rising before Lieut. Greely could speak, so great was the outburst of enthusiasm which greeted him. He remarked that he was surprised to learn that the ground did not thaw lower at Lieut. Ray’s station, which was ten degrees farther south than his own, where the ground thawed to a much greater depth–namely, twenty to thirty feet. In regard to an open polar sea, he differed from Lieut. Ray. He did not believe there was a navigable sea at the pole, but he was of the opinion that there was open water somewhere about.
The geographical work of the Lady Franklin Bay expedition covers nearly three degrees of latitude and over forty degrees of longitude. Starting from latitude 81 deg. 44 min. and longitude 84 deg. 45 min., Lieut. Lockwood reached, May 18, 1882, on the north coast of Greenland, latitude 83 deg. 24 min. and longitude 40 deg. 46 min. From the same starting point he reached to the southwest, in May, 1883, Greely Fiord, an inlet of the Western Polar Ocean, latitude 80 deg. 48 min. and longitude 78 deg. 26 min. This journey to the northward resulted in the addition to our charts of a new coast line of nearly 100 miles beyond the farthest point seen by Lieut. Beaumont, R.N. It also carried Greenland over 400 miles northward, giving that continent a much greater extension in that direction than it had generally been credited with.
In a subsequent speech he took occasion to say that a fact had surprised him. It was the discovery that when the tide was flowing from the North Pole it was found by his observations that the water was warmer than when flowing in the opposite direction. He took the trouble to have prepared an elaborate set of observations showing this wonderful phenomenon, which would eventually be published. To him these pecularities were unexplainable, and be hoped that the observations would be studied by his hearers, and some explanation found in regard to the thermometric observations of the expedition. He remarked that the mean temperature for the year of the hourly observations was 5 degrees below zero, which justified him in saying his station was the coldest point of earth ever reached.
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DIAMOND MINING IN BRAZIL.
It was in 1729 that the Portuguese government learned of the discovery of the diamond that had been made in the rivers of the environs of Diamantina by some adventurers who had entered this region in search of gold. Since that epoch the exploitation of this gem, pursued under varied regimes, and with diverse success, has never ceased. As soon as it heard of this discovery, the Portuguese government thought it would make as much profit out of it as possible, so it no longer authorized any other exploitation in the Diamantina regions than that of the diamond, and it imposed upon such exploitation a tax that was fixed at 28 francs per laborer in 1729 and 224 in 1734. From 1734 to 1739 all operations were suspended, and a more lucrative organization for the treasury was sought for. In 1739 the era of contracts was inaugurated. The exploitation of the diamond was farmed out for four years to a _contratador_, who was to work a certain territory with a number of men, fixed at 600 as a maximum, and to pay into the treasury a sum per workman (whether working or not) that varied from 1,288 francs per year in 1734 to 1,344 francs for the last contract, that ended in 1772. At this epoch the government took the exploitation of the diamond in hand, and gave it in charge of a special administration, which was submitted to the direction of the treasury of Lisbon, and which had at its head a comptroller. This new regime lasted till 1845. In order to render the surveillance of the treasury agents efficient, and prevent smuggling (which can be so easily done with an object like the diamond), it was necessary to impose a special regime over the entire region of Diamantina, and, in fact, the latter was, up to the independence of Brazil, submitted to Draconian regulations.
[Illustration: FIG. 1.–DAM ON THE RIBEIRAO INFERNO AT PORTATO DE FERRO.]
We only know the quantity of stones that were discovered during the period when operations were directed by the Royale Extraccao, from 1772 to 1845, and this was 269,870 grammes, or more than 1,300,000 carats. It should be understood that what was taken by stealth does not enter into this total, and it must be stated that during the latter years, when the Extraccao existed only in name, smuggling must have been active.
[Illustration: FIG. 2.–ARRANGEMENT OF THE MACHINERY AT THE PORTATO DE FERRO DIAMOND DEPOSITS.]
Since that epoch the exploitation has been continued by lessees of the diamondiferous grounds. It is almost impossible to estimate what the territory has produced. The discovery of the Cape deposits has given it a terrible blow. Although the Brazilian diamond is much more beautiful, and for this reason is held at a much higher price, these new exploitations, by annually throwing large quantities of stones upon the market, have led to a great reduction in the price, and the Diamantina exploitations, which have become long, difficult, and costly, have received a serious set-back. So the annual production of this region, which was estimated for the years preceding 1870 at 3,000 oitavas (about 52,000 carats), is now scarcely 500.
The rivers in the environs of Diamantina rim at the bottom of deep and narrow gorges that have been scooped out to depths of 300 or 400 meters through the denuded plateau in whose center stands the city of Diamantina. In the bed of these rivers, in places where they have not yet been worked, there may be found, underneath a stratum of modern sand, another of rocks, and finally a diamondiferous deposit of rounded pebbles, mixed with sand. This gravel, which is characterized in the first place by the fact that all its elements are rounded, and next by the presence of a large number of minerals (among which the most important are all the oxides of titanium, different oxides of iron, tourmaline, and a whole series of hydrated phosphates of complex composition), is called in the language of the country _cascalho_. It is the matrix of the diamond, and the latter is extracted from it by washing. It is arranged in roundish masses upon the beds of the rivers, and is met with at depths ranging from a few decimeters up to 25 and 30 meters.
The same material, with the same name, is also found deposited at all heights upon small terraces at the sides of the valleys through which the rivers flow. It is coarser and less rolled, and has very likely been deposited by risings of the rivers during the period when the valleys were being formed. These deposits bear the name of _gupiarras_. Finally, it is found in a still coarser state, mixed with red earth and deposited in horizontal strata upon the upper plateau. It is then called _gorgulho_.
Of these different deposits, the most important are those of the river beds, the material here having undergone a true mechanical preparation and being richer. These are the deposits that have been the object of the most important exploitations.
The year is divided into two distinct seasons–the dry, from May to September, during which rain is exceptional, and the rainy, from October to April. As water is necessary for all the operations, no work can be done upon the high plateaux except through rain water stored up in large reservoirs. These beds form what are called the “rainy season washings.” In the rivers the working of the beds requires a preliminary drying, which is effected by diverting the river’s course. Now in all this rocky and denuded region the water that falls runs immediately to the river, and causes terrible freshets therein; so operations capable of keeping the bed dry would be out of proportion to the probable results of the exploitation, whence it follows that the latter is only possible in dry weather, and these deposits are therefore called “dry season washings.”
These deposits are still worked in our day as they were in the time of the Portuguese. In order to dry the bed a dam is constructed, and the river is either diverted into a plank flume supported by piles, or into a canal dug along the shore, or by means of tight walls, according to the lay of the place. The second process, which is preferable to the first, is in fact impossible when the river runs, as is often the case, in a narrow, abrupt, walled channel. These works are sometimes very important. In 1881, the Acaba Mundo flume was 140 meters in length and 5.2 m. wide, and, with a velocity of 2.25 m., discharged 4,500 liters per second; still longer ones might be cited that discharged as much as 8,000 liters.
In the dry part of the river the extraction of the sand, stones, and cascalho is done solely by hand. The men carry the sand upon their heads in small wooden bowls called _carumbes,_ which hold about 15 kilogrammes, and throw it somewhere where the deposit will not interfere with the exploitation. Almost all of these men are negroes, who run with their load upon their head over the white sand, singing some song of their country. It, is very picturesque, but it is doubtful whether it is economical.
Since the century and a half that these rivers have been dug and redug, it may be admitted that wherever the cascalho has been easy of access it has been removed; and that wherever it has not been, little attempt has been made to work it. How have these attempts, which have doubtless been made at several periods, come out? This would at present be very difficult to ascertain. The exploitations have been too numerous to allow us now to estimate the value of a bed from the data furnished by geology, and local tradition is too uncertain or exaggerated to allow us to place much confidence in it.
We can, at the very most, say that if some points still remain intact it must be because the exploitation of them was too difficult with the processes that were employed, and this should be a reason, were it desired to attempt new operations, for having recourse to entirely different modes of work.
It would seem rational, as regards this, to try to put to profit the hydraulic power that the flumes and canals render disposable for mechanically extracting the sand. The field to be worked being naturally long and narrow, it would be the proper thing to employ a series of inclined planes distributed along the banks, actuated by water wheels, and corresponding to so many small working points. The river often flows through a genuine canon with nearly vertical walls, where space would be absolutely wanting for installing wheels elsewhere than at the exit of the canal, and if may become necessary to distribute the power of these wheels along the works. In these regions of difficult access and few resources it is necessary to dispense with complicated apparatus, and one might in such a case, it would seem, try electric motors, whose installation would be easy. An exploitation in accordance with these ideas was begun for the first time in 1883 upon the Ribeirao de Inferno at Portao de Ferro. We shall describe it.
Once established in the country, the first thing to do is to form roads so as to secure communications with the neighboring villages and forests, and afterward to cut down trees for building houses. These latter are usually constructed, for these works, of untrimmed wood and mud, with thatched roof. There were thus constructed at Portao de Ferro a few kilometers of roads, then some houses for the engineers and special workmen, barracks for 200 laborers, stores, kitchens, etc., a forge, and a shop with a lathe and a saw run by a wheel at the side. It was afterward necessary to repair the old lateral canal which had been dug out of the rock in the times of the Royal Extraction, but which had been torn open for a considerable length. This necessitated the erection of tight walls of dry stone, grass, and mud, for a length of 200 meters, and with thicknesses of from 6 to 10 meters.
In order to divert the water into this canal, it was necessary to raise its level 5 meters. The dam, then, had to support a strong pressure, and it could not be built upon sand. It therefore became necessary to build a temporary dam and to turn the river into a plank flume, so as to make it possible to dig at the location of the permanent dam in order to reach a solid bottom at a depth of nearly 4 meters. The permanent dam thus had a total height of 10 meters, with a thickness of 15 at the base and 7 at the top. It was constructed of dry stone, grass, and earth, with the addition of strong wood-work. The rocks upon which it had to be built were full of fissures, and when it was desired to close it great leakages of water occurred, which came near ruining it and necessitated the construction of a second wall behind it and a talus of earth in front. The dam as shown in Fig. 1, when finished, had a thickness of 25 meters at the base. It was closed on the second of July, and had a storage capacity of 55,000 cubic meters.
The principal excavation was begun at the point where the bed was deepest, and which consequently the older miners must have had most trouble in reaching. Here were set up two Letestu pumps that were actuated by a four-horse wheel.
These pumps lifted 50 cubic meters per hour. All except the pump chambers and pipes was made of wood on the spot. The water that was lifted was carried away from the works in a flume 160 meters in length, which likewise removed the water from the motive wheels.
For the service of the same excavation two simple acting inclined planes were installed that were moved by a four-horse wheel. Fig. 2 gives a general view of the arrangement.
The tracks of these planes were made of wood. Steel rails, however, had been brought for the cars, along with the cables and the metallic parts of the windlass; but all else was made upon the spot, including all the wooden pulleys for transmitting motion from the wheel to the windlasses.
This excavation reached bottom at a depth of 16 meters. The second touched bottom at about 10 meters, and gave access to a subterranean canal, which was followed for about 20 meters. The extraction of sand was effected here by an inclined plane moved by a Gramme machine. The generatrix had to make 1,500 revolutions, and be set in motion by an overshot wheel. As time was wanting, it became necessary to diminish to as great a degree as possible the number of parts to be employed in the transmission of motion, and since there was an abundance of water, a velocity of 15 revolutions was accepted for the wheel, which, with a total fall of 4.8 meters, had to give a power of eight horses. A three meter pulley was placed upon the shaft of the wheel. This was made of freshly cut wood that had been exposed to the sun. In order to give it sufficient stability and prevent its warping, it was placed against the wheel in such a way as to rest upon the latter’s spokes. This rendered it necessary to give up the idea of using a belt, since it was not possible to prevent its getting wet. Cords could not be found in the country, and so it was necessary to make use of a too heavy chain, which was in no wise intended for such a purpose, and which at a velocity of 15 revolutions began to swing and necessarily absorbed much power. The large pulley drove one of 0.4 m. upon an intermediate shaft. Upon this latter a 2.6 m. wooden pulley directly drove, through a belt, the 0.2 m. pulley of the generatrix.
From this may be judged what the country’s resources are. The motor, by means of a belt, actuated a windlass provided with suitable checking gearings. The distance of the two machines was 116 meters. Save the transmission by chain, the whole worked in a satisfactory manner. The performance could only be estimated in a lump, by comparing on the one hand the theoretical work of the fall of water, and, on the other, that of the vertical elevation of the car; and, further, one was obliged to estimate the weight of the latter. If we allow 1,000 kilogrammes for the weight of a car that received 360 liters of dry sand or 300 of wet, the performance was 19 per cent., and appeared to be satisfactory, considering the conditions under which the installation was made. This experiment was at all events of such a nature as to indicate the use of these machines in cases where the arrangement of the locality absolutely necessitates a transmission of power.
The first workmen reached Portao de Ferro December 15, 1882, and the material shipped from France did not arrive until April 25, 1883. Operations were suspended about the 25th of September, since, for a fortnight already, there had no longer been any doubt as to the manner in which the river bed had been cleaned by former operators.
As a result of this first experiment, the proof remained that it would be easy in future exploitations to introduce into the country methods of work that are quicker and more economical than those now in use. In fact, all the operations were performed with natives of the country, with the exception of a carpenter and blacksmith from Rio Janeiro.–_La Nature._
* * * * *
WHAT WE REALLY KNOW ABOUT ASIATIC CHOLERA.
NEW YORK, September 1, 1884.
_To the Editor of the New York Medical Journal_:
SIR: I have been exceedingly interested in Dr. Bartlett’s suggestive article in your issue of August 30. But a sufficient number of well-established facts are known to account for all the peculiarities and vagaries of cholera.
1. Cholera has existed in Hindostan for centuries. It was found there by Vasco da Gama in 1496, and there is a perfectly authentic history of it from that time down to the present.
2. It is never absent from India, from whence it has been conveyed innumerable times to other countries. It has never become domiciled in any other land, not even in China, parts of which lie in the same latitude; nor in Arabia, to which country pilgrims go every year from India; nor in Egypt, nor Persia, with which communication is so frequent; much less in any other part of the world. Canton in China, Muscat and Mecca in Arabia, lie nearly in the same degree of latitude as Calcutta, in which cholera is always existent; yet these places only have cholera occasionally, and then only after arrivals of it from Hindostan.
3. The arrival of cholera in other countries is often involved in some easily removable obscurity, which is deepened only by the ignorance and want of veracity of quarantine and other officials.
4. Cholera is almost always preceded by a premonitory diarrhoea, which lasts from one or two to three or four or more days before urgent and characteristic symptoms show themselves. Of 6,213 cases, no less than 5,786 had preceding diarrhoea. The sufferers from this sow the germs of the disease in numerous, often distant and obscure, places, to which no choleraic person is supposed to have come.
5. The discharges swarm with infective bacteria of various kinds, some of which, especially Koch’s comma bacilli, seem to be specific.
6. The disease has been reproduced in men and some few animals by their swallowing the discharges.
7. The discharges, according to the experiments of Thiersch, Burdon-Sanderson, and Macnamara, are not virulent and poisonous for the first twenty-four hours; on the second day eleven per cent. of those who swallow them will suffer; on the third day, thirty-six per cent.; on the fourth day, ninety per cent.; on the fifth day, seventy-one per cent.; on the sixth day, forty per cent.; and after that the discharges have no effect–the bacteria die, and the poison becomes inert.
Professor Robin reproduced cholera in dogs, and the celebrated dog Juno died of cholera in Egypt last year. Professor Botkin, of the University of Dorpat, reproduced cholera in dogs by the subcutaneous injection of the urine of cholera patients. Even if the comma bacilli are not found in the urine, other bacteria are; and even Koch supposes that they secrete a virulent poison similar to that of some insects, which may be absorbed into the blood and escape from the kidneys.
8. Some of the manners and customs of the Hindoos are very peculiar. They always defecate upon the open ground, and will not use privies or latrines This is a matter of religious obligation with them. It is also obligatory upon them to go to stool every morning; to use the left hand only in wiping themselves; to wash their fundaments after stool; to wash their whole persons and clothing every day; and, finally, also to rinse their mouths with water, and this they often do after washing in foul tanks, or still fouler pools of water. On steamships, where tubs of water were provided for washing their fundaments after defecation, Surgeon-General De Renzy saw many Hindoos rinse their mouth with the same water.
9. The population of Hindostan is nearly three hundred millions, and at least one hundred million pounds of faecal matter is deposited on the open ground everyday, and has been for centuries.
10. Much of this foul matter is washed by rains into their tanks and pools of water, which they use indiscriminately for washing, cooking, and drinking purposes.
11. The poison of cholera has repeatedly been carried in soiled clothing packed in trunks and boxes, and conveyed to great distances.
12. Articles of food, even bread and cake, as well as apples, plums, and other fruit, handled by persons in the incipient stages of cholera, have been known to convey the disease.
13. The number of epidemics produced by cholera discharges getting into drinking water are almost innumerable, and those from contaminated milk are not few.
14. The first case of cholera is generally counted from the first fatal one, whereas this is almost always preceded by non-fatal ones, which have escaped notice. And each subsequent fatal case is interwoven by one, or several, or even many, non-fatal causes. If the string of a row of beads is broken, and the beads scattered everywhere, it would be just as improper to say that they had never been upon a string as to say that, because all the fatal cases of cholera cannot be traced to equally fatal ones, no connection ever existed between them.
These points are necessarily stated categorically, but every one can be proved, if proof is called for. The numerous and very large pilgrimages of the Hindoos must not be forgotten.
John C. Peters, M.D.
83 Madison Avenue.
* * * * *
DR. KOCH ON THE CHOLERA.
An important and influential conference[1] upon cholera was opened in Berlin at the Imperial Board of Health on the evening of July 26. There were present Drs. v. Bergmann, Coler, Eulenbrg, B. Fraenkel, Gaffky, Hirsch, Koch, Leyden, S. Neumann, Pistor, Schubert, Skreczka, Struck, Virchow, and Wollfhuegel. The conference had been called at the instance of the Berlin Medical Society, whose President, Prof. Virchow, explained that it was thought advisable Dr. Koch should, in the first instance, give a demonstration of his work before a smaller body than the whole society, so that the proceedings might be fully reported in the medical press. He mentioned that Herr Director Lucanus and President Sydow had expressed their regret at being unable to be present, as well as many others, including Drs. Von Lauer, Von Frerichs, Mehlhausen, and Kersaudt. Before the meeting Dr. Koch exhibited microscopical specimens and drawings of the cholera bacillus, and demonstrated the method of its preparation and cultivation. The preparations included specimens of choleraic dejections dried on covering glasses, stained with fuchsin or methyl-blue, and examined with oil immersion, one-twelfth, and Abbe’s condenser; also sections of intestine preserved in absolute alcohol, and stained with methyl-blue. There were also cultures in gelatin, etc.
[Footnote 1: A detailed report is published in the _Berliner Klinische Wochenschrift_ Aug. 4.]
Dr. Koch commenced by remarking that what was required for the prevention of cholera was a scientific basis. Many and diverse views as to its mode of diffusion and infection prevailed, but they furnished no safe ground for prophylaxis. On the one hand, it was held that cholera is a specific disease originating in India; on the other, that it may arise spontaneously in any country, and own no specific cause. One view regards the infection to be conveyed only by the patient and his surroundings; and the other that it is spread by merchandise, by healthy individuals, and by atmospheric currents. There is a like discrepancy in the views on the possibility of its diffusion by drinking water, on the influence of conditions of soil, on the question whether the dejecta contain the poison or not, and on the duration of the incubation period. No progress was possible in combating the disease until these root questions of the etiology of cholera are decided.
Hitherto the advances in knowledge upon the etiology of other infective diseases have done little toward the etiology of cholera. These advances have been made within the last ten years, during which time no opportunity–at least not in Europe–has occurred to pursue researches; and in India, where there is abundant material for such research, no one has undertaken the task. The opportunity given by the outbreak of cholera in Egypt last year to study the disease before it reached European soil was taken advantage of by various governments, who sent expeditions for the purpose. He had the honor to take part in one of these, and in accepting it he well knew the difficulties of the task before him, for hardly anything was known about the cholera poison, or where it should be sought; whether it was to be found only in the intestinal canal, or in the blood, or elsewhere. Nor was it known whether it was of bacterial nature, or fungoid, or an animal parasite–e.g., an amoeba. But other difficulties appeared in an unexpected direction. From the accounts given in text-books he had imagined that the cholera intestine would show very slight changes, and would be filled with a clear “rice-water” fluid. He had not fully recollected the conditions met with in post-mortem examinations had formerly made, and was therefore at first surprised to meet with quite a different state of things. For he soon found that in a large majority of cases remarkably severe lesions were present in the intestines. In other cases the changes were slighter, and eventually he met with some which, to a certain extent, corresponded with the type described in text-books. But it was some time, and after many inspections, before he was enabled to correctly interpret the varied changes met with. In spite of a most careful examination of all other organs and of the Mood, nothing was found to establish the presence of an infective material, and attention was finally concentrated on the intestinal conditions.
There were cases in which the lower segment of the small intestine, most marked immediately above the ileocaecal valve, extending thence upward, was of a dark reddish-brown color, the mucous membrane being covered with superficial haemorrhages. In many cases the mucous membrane appeared to be superficially necrosed, and covered with diphtheritic patches. The intestinal contents in such cases were not colorless, but consisted of a sanguinolent, ichorous, putrid fluid. Other cases showed a gradual transition to a less marked change. The redness was less intense, and was in patches, while in others the injection was limited to the margins of the follicular and Peyerian glands, giving an appearance which is quite peculiar to cholera. In comparatively few cases were the changes so slight as to consist in a somewhat swollen and opaque condition of the superficial layers of the mucous membrane, with delicate rosy-red injection, and some prominence of the solitary follicles and Peyer’s patches. In such cases the intestinal contents were colorless, but resembling meal-soup rather than rice-water. In only a solitary instance were the contents watery and mucoid. Microscopical examination of the intestine and its contents revealed, especially in the cases where the margins of Peyer’s patches were reddened, a considerable invasion of bacteria, occurring partly within the tubular glands, partly between the epithelium and basement membrane, and in some parts deeper still. Then he found cases in which, besides bacteria of one definite and constant form, there were others also accumulated within and around the tubular glands, of various size, some short and thick, others very fine; and be soon concluded that he had to do here with a primary invasion of pathogenic bacilli, which, as it were, prepared the tissues for the entrance of the non-pathogenic forms, just as he had observed, in the necrotic, diphtheritic changes in the intestinal mucosa and in typhoid ulcers.
Passing to speak of the microscopical character of the contents of the bowel, Dr. Koch said that owing to the sanguinolent and putrescent character of these in the cases first examined, no conclusion was arrived at for some time. Thus he found multitudes of bacteria of various kinds, rendering it impossible to distinguish any special forms, and it was not until he had examined two acute and uncomplicated cases, before haemorrhage had occurred, and where the evacuation had not decomposed, that he found more abundantly the kind of organism which had been seen so richly in the intestinal mucosa. He then proceeded to describe the characters of this bacterium. It is smaller than the tubercle bacillus, being only about half or at most two-thirds the size of the latter, but much more plump, thicker, and slightly curved. As a rule, the curve is no more than that of a comma (,) but sometimes it assumes a semicircular shape, and he has seen it forming a double curve like an S, these two variations from the normal being suggestive of the junction of two individual bacilli. In cultures there always appears a remarkably free development of comma shaped bacilli. These bacilli often grow out to form long threads, not in the manner of anthrax bacilli, nor with a simple undulating form, but assuming the shape of delicate long spirals, a corkscrew shape, reminding one very forcibly of the spirochaete of relapsing fever. Indeed, it would be difficult to distinguish the two if placed side by side. On account of this developmental change, he doubted if the cholera organism should be ranked with bacilli; it is rather a transitional form between the bacillus and the spirillum. Possibly it is a true spirillum, portions of which appear in the comma shape, much as in other spirilla–_e. g_., spirilla undula, which do not always form complete spirals, but consist only of more or less curved rods. The comma bacilli thrive well in meat infusion, growing in it with great rapidity. By examining, microscopically, a drop of this broth culture the baccilli are seen in active movement, swarming at the margins of the drop, interspersed with the spiral threads, which are also apparently mobile. They grow also in other fluids–_e. g_., very abundantly in milk, without coagulating it or changing its appearance. Also in blood serum they grow very richly.
Another good nutrient medium is gelatine, wherein the comma bacilli form colonies of a perfectly characteristic kind, different from those of any other form of bacteria. The colony when very young appears as a pale and small spot, not completely spherical as other bacterial colonies in gelatine are wont to be, but with a more or less irregular, protruding, or jagged contour. It also very soon takes on a somewhat granular appearance. As the colony increases, the granular character becomes more marked, until it seems to be made up of highly refractile granules, like a mass of particles of glass. In its further growth the gelatine is liquefied in the vicinity of the colony, which at the same time sinks down deeper into the gelatine mass, and makes a small thread-like excavation in the gelatine, in the center of which the colony appears as a small white point. This again is peculiar; it is never seen, at least so marked, with any other bacterium. And a similar appearance is produced when gelatine is inoculated with a pure culture of this bacillus, the gelatine liquefying at the seat of inoculation, and the small colony continually enlarging; but above it there occurs the excavated spot, like a bubble of air floating over the bacillary colony. It gives the impression that the bacillus growth not only liquefies the gelatine, but causes a rapid evaporation of the fluid so formed. Many bacteria also have the power of so liquefying gelatine with which they are inoculated, but never do they produce such an excavation with the bladder-like cavity on the surface.
Another peculiarity was the slowness with which the gelatine liquefied, and the narrow limits of this liquefaction in the case of a gelatine disk. Cultures of the comma bacillus were also made in agar-agar jelly, which is not liquefied by them. On potato these bacilli grow like those of glanders, forming a grayish-brown layer on the surface. The comma bacilli thrive best at temperatures between 30 deg. and 40 deg. C., but they are not very sensitive to low temperatures, their growth not being prevented until 17 deg. or 16 deg. C. is reached. In this respect they agree with anthrax bacilli. Koch made an experiment to ascertain whether a very low temperature not merely checked development but killed them, and subjected the comma bacilli to a temperature of 10 deg. C. They were then completely frozen, but yet retained vitality, growing in gelatine afterward. Other experiments, by excluding air from the gelatine cultures, or placing them under an exhausted bell jar, or in an atmosphere of carbonic acid, went to prove that they required air and oxygen for their growth; but the deprivation did not kill them, since on removing them from these conditions they again began to grow.
The growth of these bacilli is exceptionally rapid, quickly attaining its height, and after a brief stationary period as quickly terminating. The dying bacilli lose their shape, sometimes appearing shriveled, sometimes swollen, and then staining very slightly or not at all. The special features of their vegetation are best seen when substances which also contain other forms of bacteria are taken–_e. g_., the intestinal contents or choleraic evacuations mixed with moistened earth or linen and kept damp. The comma bacilli in these conditions multiply with great rapidity so as to far outnumber the other forms of bacteria, which at first might have been in far greater abundance. This state of affairs does not last long; in two or three days the comma bacilli began to die off, and the other bacteria began to multiply. Precisely the same thing takes place in the intestine, where, after the rapid initial vegetation is over, and when exudation of blood occurs in the bowel, the comma bacilli disappear and putrefactive bacteria predominate. Whether the occurrence of putrefaction is inimical to the comma bacilli has not been proved, but from analogy it is very probable. At any rate, it is important to know this for certain, for if it be so, then the comma bacilli will not thrive in a cesspit, and then further disinfection would be unnecessary. These bacilli thrive best in fluids containing a certain amount of nutriment. Experiments have not yet shown the limits in this respect, but Koch has found them capable of growing in meat broth diluted ten times.
Again, if the nutrient medium become acid in reaction their growth is checked, at least in gelatine and meat infusion; but singularly enough, they continue to grow on the surface of a boiled potato which has become acid, showing that all acids are not equally obnoxious to them. But here, as with other substances which hinder their growth, they do not kill the bacilli. Davaine has shown that iodine is a strong bactericide. He experimented with anthrax bacilli in water to which iodine was added, and the bacilli were destroyed. But practically the organisms have to be dealt with in the alkaline contents of the bowel, or in the blood or fluids of the tissues, where iodine cannot remain in the free state. Koch found that the addition of an aqueous solution of iodine (1 in 4,000) to meat infusion, in the proportion of 1 in 10, did not in the least interfere with the growth of the bacilli in that medium. He did not pursue this line of inquiry, seeing that in practice larger quantities of iodine than that could not be given. Alcohol first checks the development of the comma bacilli when it is mixed with the nutrient fluid in the proportion of 1 in 10, a degree of concentration which renders it impracticable for treatment. Common salt was added to the extent of 2 per cent. without influencing the growth of the bacilli. Sulphate of iron, in the proportion of 2 per cent., checks this growth, probably by precipitating albumimites from the fluids, and possibly also by its acid reaction; certainly it does not seem to have any specific disinfecting action–i.e., in destroying the bacilli. Indeed, Koch thinks that the admixture of sulphate of iron with faecal matter may arrest putrefaction, and really remove what may be the most destructive process to the comma bacilli. Hence he would distinguish between substances which merely arrest putrefaction and those which are bactericidal; for the former may simply serve the purpose of preserving the infective virus. Among other substances which prevent the growth of the comma bacilli may be mentioned alum, in solutions of the strength of 1 in 100; camphor, 1 in 300; carbolic acid, 1 in 400; oil of peppermint, 1 in 2,000; sulphate of copper, 1 in 2,500 (a remedy much employed, but how much would really be needed merely to hinder the growth of the bacilli in the intestine!); quinine, 1 in 5,000; and sublimate, 1 in 100,000. In contrast with the foregoing measures for preventing the growth of these bacilli is the striking fact that they are readily killed by drying. This fact is proved by merely drying a small drop of material containing the bacilli on a cover-glass, and then placing this over some of the fluid on a glass slide. With anthrax bacilli vitality is retained for nearly a week; whereas, the comma bacillus appears to be killed in a very short time. Thus it was found that although vitality was retained–depending largely upon the number of bacilli–for a short time, yet withdrawal of the nutrient fluid for an hour or even less often sufficed; and it never happened that the bacilli retained vitality after a deprivation lasting twenty-four hours. These results would seem to point to the fact that the comma bacillus does not, like the organisms of anthrax and vaccinia, pass into the resting state (Daner-zustande) by drying; and if so, it is one of the most important facts in the etiology of cholera. Much, however, remains to be done, especially with regard to the soiled linen of cholera patients being kept in a damp state. He found that in soiled articles, when dried for a time, varying from twenty-four hours and upward, the comma bacilli were quite destroyed. Nor was the destruction delayed by placing choleraic excreta in or upon earth, dry or moist, or mixed with stagnant water. In gelatine cultures the comma bacilli can be cultivated for six weeks, and also in blood serum, milk, and potato, where anthrax bacilli rapidly form spores. But a resting state of the comma bacilli has never been met with–a very exceptional thing in the case of bacilli, and another reason why the organism must be regarded rather as a spirillum than a bacillus, for the spirilla require only a fluid medium, and do not, like the anthrax bacilli, thrive in a dry state. It is quite unlikely that a resting state of the comma bacillus will ever be discovered; and, moreover, its absence harmonizes with our knowledge of cholera etiology.–_The Lancet_.
* * * * *
[THE MEDICAL RECORD.]
MALARIA.–THE NATURAL PRODUCTION OF MALARIA, AND THE MEANS OF MAKING MALARIAL COUNTRIES HEALTHIER.
[Footnote: An Address delivered at the Eighth Session of the International Medical Congress, Copenhagen, August 12, 1884.]
By Conrad Tommasi Crudeli, M.D., Professor of Hygiene, University of Rome, Italy.
Before entering upon my subject, I must crave the indulgence of those of my colleagues whose language I have borrowed for any italicisms that I may use, as well as for the foreign accent which must strike their ears more or less disagreeably. Desiring to respond as well as lay in my power to the invitation with which I have been honored to discuss the hygienic questions relating to malaria, I have chosen the French language as being the one in which, apart from my mother tongue, I could express myself with the greatest ease and precision.
I shall be pardoned also, I hope, for having employed the terms “malaria” and “malarial districts” in place of the more commonly used expressions “paludal miasm” (_miasme paludeen_) and “marshy regions” (_contrees marecageuses_). The substitution is not a happy one from a literary point of view, but I have made it deliberately and for the following reason: The idea that intermittent and pernicious fevers are engendered by putrid emanations from swamps and marshes is one of those semi-scientific assumptions which have contributed most to lead astray the investigations of scientists and the work of public administrations. This idea, so widespread and so well established by the traditions of the school, is radically false. The specific ferment which engenders those fevers by its accumulation in the atmosphere which we breathe is not exclusively of paludal origin, and still less is it a product of putrefaction. Indeed, in every region of the globe between the two Arctic circles there are swamps and marshes, steeping-tanks of hemp and flax, large deltas where salt and fresh waters mix, and yet there is no malaria there, although putrid decomposition is on every side. On the other hand, in the same parts of the globe there are places which are not and never were marshy, and in which there is not the least trace of putrefaction, but which, nevertheless, produce malaria in abundance. I reject, therefore, wholly the paludal assumption, and in order to express this view in the title of my paper, have been forced to employ terms which to my hearers may sound like italicisms.
The Italians generally have not this paludal notion, for experience taught them long ago that malaria is produced nearly everywhere–in marshy districts as well as in those which might almost be called arid; in a volcanic soil as well as in the deposits of the Miocene and Pliocene periods and the ancient and modern alluvia; in a soil rich in organic matters as well as in one containing almost none; in the plains as well as on the hills or mountains. The word malaria (bad air), which it is the sad privilege of Italy to have lent to all languages to express the cause of intermittent and pernicious fevers, represents, then, among the majority of our rural populations, the idea of an agent which may infect any sort of country, whatever may be its hydraulic and topographical conditions, and whatever may be its geological formation. This word, therefore, is the one best suited to designate this specific ferment in question, and I have on this account, employed it and its adjectival derivatives in order not to resuscitate the idea of the exclusively paludal origin of the morbific agent.
I shall not tarry long to speak of the nature of this ferment, for the studies bearing upon that point, although far advanced, are not yet completed. I may remark, however, that the idea that the ferment is formed of living organisms is a very old one, and has not arisen suddenly because of the modern theories of the parasitic nature of disease. From the time of Varrar (who believed that malaria was made up of invisible mites suspended in the atmosphere) to our own day this theory has been several times advanced by hygienists. Independently of the general considerations which led Rasori, and later Henle, to formulate the doctrine of the _contagium vivum_ of infection (long before the progress of microscopical science had revealed the existence of living ferments), there were peculiar circumstances as regards malaria which should have impelled minds to look in that direction, even in times long past.
Some of these circumstances are of a nature to strike every serious observer, and deserve a few moments’ attention. How could one maintain, for example, that this ferment is a product of chemical reactions taking place in the ground, when it is seen to remain constantly the same whatever may be the composition of the soil from which it emanates! As long as the paludal theory held sway, the chemical interpretation of this identity of the product in every latitude was easy. Rica does not hesitate to admit that when a swampy tract is heated by the sun’s rays to the necessary point for the putrid decomposition of the organic matters contained in it, the “chemical ferment,” or rather the “mephitic gases,” to which is attributed the morbific action, are developed, whatever may be the distance from the equator at which this marshy region lies. But since it has been ascertained that malaria is produced in soils of the most varied chemical composition, _the persistent identity of this product_ has become chemically inexplicable; while it is however readily conceivable, if one admits that malaria is an organized ferment which easily finds the necessary conditions for its life and multiplication in the most varied soils, as is the case with millions of other organisms vastly superior to the rudimentary vegetables which constitute the living ferments.
The same thing may be said of _the progressive intensity of the morbific production in abandoned malarious districts_. This fact has been historically proved in several parts of the earth, and especially in Italy. A large number of Grecian, Etruscan, and Latin cities, even Rome itself, sprang up in malarious territories and attained a high state of prosperity. First among the reasons for this success must be placed the works undertaken with a view of rendering these places more salubrious, and which lessened the evil production, _but almost never extinguished it completely_. After the abandonment of these localities, the production of malaria recommenced in a degree which went on increasing from age to age, and which has rendered some of these places actually uninhabitable. This was seen, in the time of the ancient Romans, in Etruria, when it was conquered and laid waste, and in several parts of Magna Graecia, and of Sicily. From the fall of Rome even to the present day, this phenomenon has been manifested in a very evident manner in the Roman Campagna, in certain parts of which, even up to the time of the Renaissance, it was possible to maintain pleasure houses, but which are now unhabitable during the hot season. In many cases the physical conditions of the soil have undergone no appreciable change during centuries, so that it is impossible to attribute so enormous an augmentation of malaria to an increase in its annual production, itself increased by a progressive alteration of the chemical composition of the soil. But if, on the contrary, it be admitted that malaria is caused by a living organism whose successive generations accumulate in the soil, the interpretation of this fact becomes very simple.
There are, finally, _peculiarities in the local charging of the atmosphere with malaria_ which can be explained only in this manner. If the malarial miasm were composed of gaseous bodies emanating from the soil, or rather of chemical ferments formed beneath the ground and raised into the air by gases or watery vapor, the charging of the atmosphere with the specific poison ought to arrive at its maximum during the hottest part of the day, when the ground is heated the most by the sun’s rays, and when the evaporation of water and all chemical actions attain their maximum intensity. But this is very different from what actually occurs. The local charging of the atmosphere is always less strong during the meridian hours than at the beginning and the end of the day, that is to say, after the rising, and especially after the setting, of the sun. Now it is precisely at these hours that the difference between the temperature of the lower layers of the atmosphere and that of the surface of the ground is the greatest, and that the ascending currents of air starting from the ground are the strongest. If malaria consists of solid particles contained in the soil, one may readily understand how their elevation _en masse_ into the atmosphere should take place especially at these two periods of the day.
All these facts, which can be easily verified if the subject of malaria be studied on the spot and without any preconceived notions, explain the tendency which has always been manifested to attribute this specific poisoning of the air to a living organism which is multiplied in the soil; and they also explain the ardor with which hygienists have applied themselves to the production of the scientific proof.
Unfortunately the investigations undertaken for this end have for a long time been fruitless, for the preconceived paludal theory has led investigators to occupy themselves exclusively with the inferior organisms inhabiting marshes. Among these organisms they studied especially the _hyphomycetes,_ which had already acquired so great an importance in dermatology; and their entire attention was concentrated upon the aquatic algae, without even taking the precaution to determine whether the varieties which they thought to be malarial were found in all malarious swamps, or whether they were capable of living within the human organism. It has thus happened that each observer has indicated as the cause of malaria a different variety of alga, whichever he found to be most abundant in the swampy ground that he had to examine. Thus Salisbury has indicated the _palmella gemiasma,_ which is found with us in places perfectly free from malaria, while it is often wanting in malarious marshes in the center of Italy; Balestra, a species of alga which is as yet indeterminate; Bargellini, the _palmogloea micrococca;_ Safford and Bartlett, the _hydrogastrum granulatum;_ and Archer, the _chitonoblastus oeruginosus_. There is not a single one of these species the parasitic nature of which has been demonstrated; and as regards the two last named varieties, it can be positively denied that they are capable of producing a general infection, for the diameter of their spores and filaments is greater than that of the capillary blood vessels.
It was only in 1879 that Klebs and myself, after having been thoroughly freed, by a long series of preparatory studies, from the unfortunate paludal idea, undertook together some investigations in malarious districts of the most varied character, marshy and not marshy. We employed the system of fractional cultivation, making experiments on animals with the final products thus obtained. We felt ourselves justified in recognizing the malarial ferment in the _schizomycete bacillus_. The numerous researches made subsequently by us, and by many other observers, in the soil and in the air of several malarious localities, as well as in the blood and in the organs of men and animals specifically infected, have put it henceforth almost beyond doubt that we really have to do with a schizomycete. Very recently, MM. Marchiafava and Celli have succeeded in demonstrating that the germs of this schizomycete attack directly the red blood-globules, and destroy them, causing them to undergo a series of very characteristic changes which admit of easy verification, and which render certain the existence of a malarial infection.
Several observations made recently in Rome tend to demonstrate that the schizomycete of malaria does not always assume the complete bacillary form described by Klebs and myself; but this morphological question possesses no further interest for the hygienist. For him the essential thing is to know that he has to deal with a living ferment which can flourish in soils of very varied composition, and without the presence of which neither marshes nor stagnant pools of water are capable of producing malaria.
We must not think, however, that all earth containing this ferment is capable of poisoning the superjacent atmosphere. Popular experience, certain modern scientific investigation, and the facts which one can often verify when the soil, which was malarious in ancient times and which has since ceased to be so, is turned up to a great depth, all agree in proving that the ground remains inoffensive as long as it is not placed in certain conditions indispensable for the multiplication of this specific ferment. Up to this point the organism lives, so to speak, in an inert state, and may remain so during centuries without losing any of its deleterious power. There is nothing in this fact that ought to surprise us, since we know that the life and the power of evolution belonging to the seeds of plants of a much higher order than these vegetable organisms constituting ferments, may remain latent for centuries, and may then revive at once when these grains are placed in the conditions suitable for their germination.
Among the conditions favorable to the multiplication of the malarial ferment contained in the soil, and to its dispersion through the superjacent atmosphere, there are three which are absolutely essential, and the concurrence of which is indispensable for the production of bad air (malaria). First, a temperature which does not fall below 20 deg.C. (67.5 deg.F.); next, a very moderate degree of permanent humidity of the soil; and finally, the direct action of the oxygen of the air upon the strata of earth which contain the ferment. If a single one of these three conditions be wanting, the development of malaria becomes impossible. This is a point of prime importance in the natural history of malaria, and it gives us the key to most of the methods of sanitary improvement attempted by man.
Let us see first what can be done in this direction without the labor of man. For nature herself makes localities salubrious by _suspending_ for a greater or less time the production of malaria. It is thus that winter brings about in every country a freedom from malaria which is _purely thermic_, for it is due simply and entirely to a sinking of the temperature below the required minimum. Indeed, if the temperature in winter rises above this minimum, there are often sudden outbreaks of malaria. Sometimes, during very warm and dry summers, the heat extracts all the humidity from the malarious soil, and thus procures for us a freedom from the disease which is _purely hydraulic_. This may continue for a long time (as happened in the Roman Campagna during the years 1881 and 1882), but may also be completely destroyed by a single shower. Nature also sometimes renders a district healthy in a manner _purely atmospheric_, by covering a malarious soil with earth which does not contain the malarial ferment, or with a matting formed of earth and the roots of grasses growing closely together in a natural meadow.
In the attempts of purification by suspending the malarial action, which have been devised by man, the same thing has been done; that is to say, it has been sought, to eliminate at least one of the three conditions essential to the development of the specific ferment contained in the infected soil. Naturally, they have not thought of bringing about a thermic purification, such as nature produces in winter, because of the impossibility of moderating the action of the sun; but they have tried from all time to procure hydraulic or atmospheric purifications, and sometimes to combine these together in a very happy way.
The hydraulic systems are very numerous, for the problem which is presented, namely, that of depriving the ground of its humidity during the hot season, necessitates different solutions according to the nature and the bearing of the soil. Sometimes this is done by digging open or closing ditches intended to draw away large bodies of water. At other limes a system of drainage is established, by means of which the water is drawn out of the earth and its level is depressed, so that the upper malarious strata, exposed to the direct action of the air, are deprived of moisture during the hot season. This system of drainage is not a modern invention; the Italian monks understood it as well as, and even better than, we do. In deep and loose soils they used sometimes, just as we do now, porous clay pipes; but when the subsoil was formed of compact and nearly impermeable matters, they employed a system of drainage, the extent and grandeur of which astonishes us. It is that of drainage by cavities, applied by the Etruscans, Latins, and Volsci to all the Roman hills formed of volcanic tufa, the tradition of which I have found still preserved in some countries of the Abruzzi.
We may sometimes establish a double drainage, from below and from above; that is to say, to drain the subsoil, and at the same time increase the evaporation of water from the surface of the ground. It is well known that clearing off the forests of malarious countries has often proved an excellent means of making lands salubrious which were before too damp; for, by removing every obstacle to the direct action of the sun’s rays upon the ground, we cause an increase of evaporation from its surface, and may thus be enabled to exhaust the superficial strata completely of their water during the hot season. In very moist lands, which lend themselves readily to deep drainage, the combination of the latter with a clearing of the surface has, in almost every quarter of the globe, rendered possible a very widespread and sometimes a quite lasting freedom from malaria. But, although a nearly universal experience proclaims this fact, there is a school which, following in the footsteps of Lancisi, maintains the contrary opinion, that it is necessary to preserve the forests in malarious districts, and even to increase their extent, since the trees filter the infected atmosphere and arrest the malaria in their foliage. This strange theory was formulated by Lancisi in 1714, on the occasion of the proposed clearing of a forest belonging to the Caetani family, and lying between the Pontine Marshes and the district of Cistema. Lancisi was completely imbued with the paludal notion, and consequently believed that the very severe malaria of Cistema was brought by the winds from the coast marshes, instead of being produced in the soil surrounding the district, which was then covered by this forest. He believed then that the forest acted as a protective rampart, and he prevented its being cut down. But toward the middle of the present century the Caetani had the woods cleared off from the entire belt of land surrounding Cistema. Twenty years later I was able to show that Cistema had gained greatly in salubrity. I published my observation in 1879, and, naturally, was taken to task rather sharply in the name of the sacred tradition. Happily these recriminations led our Minister of Agriculture to have the question studied by a special commission. This commission, after a conscientious examination extending over three years of all the malarious localities in the province of Rome, has just published its report,[1] the conclusions of which are entirely in accord with the facts of universal experience. They were not able to verify a single fact in support of Lancisi’s theory, while they found many of the same nature as that of Cistema, and which have resulted in overturning the theory entirely.
[Footnote 1: Della influenza dei boshi sulla malaria dominante nella regiona marittima della provincia di Roma. Annali di Agricoltura, No. 77, 1884. Roma: Eredi Botta.]
It has also been thought possible to practice drainage from above by means of plantations of certain trees which would draw considerable moisture from the earth, a method which might really be serviceable in some malarious districts. But in accordance with the idea that malaria is a product of paludal decomposition, the trees selected have almost always been the _eucalyptus_. It has been maintained that trees of so rapid a growth ought to drain the soil very actively, and also that the aroma of their foliage ought to destroy the miasmatic emanations. I have hitherto been unable to verify a single instance of the destruction of malaria by eucalyptus plantations, but I do not consider myself justified in denying the facts which have been stated by others. There is nothing to oppose the admission that these plantations, when properly made, may sometimes have been of great utility. I maintain frankly, however, that they have not always been so, and that it is necessary to guard against the exaggerations into which some have allowed themselves to fall in recent times. Such exaggerations might have been avoided if, instead of talking about these plantations on the basis of a theoretical assumption, the results only had been studied in places where the eucalyptus abounds. It would then have been known that even in the southern hemisphere, the original home of the eucalyptus, there are eucalyptus forests which are very malarious. This fact has been demonstrated by Mr. Liversige, professor in the University of Sydney, Australia. Among us also, although everybody was convinced by the statements of the press that the locality of the Tre Fontaine, near Rome, had been freed from malaria by means of the eucalyptus, people were disagreeably surprised by an outbreak of very grave fever occurring throughout the whole of this colony in 1882, a year in which all the rest of the Roman Campagna enjoyed an exceptional salubrity. If, alongside of these hygienic uncertainties, we place the agricultural uncertainties, we must conclude that it is necessary to contend strongly against this fanatical prejudice in favor of the eucalyptus tree. These plants are, in fact, very capricious in their growth. In full vegetation during the winter in our climate, they are often killed instantly by a sharp winter frost, by damp cold, by the frosts of spring, or by other causes which the botanists have not yet been able to determine. At other times, if the winters are very mild, these plants grow too rapidly in height, and then are broken short off by moderately strong winds. It should further be mentioned that these plantations are sometimes very expensive. In fact, if the earth contains too much water, it must be drained under penalty of seeing the roots of the eucalyptus rot. Then again, if the subsoil is compact, it is necessary to dig deep trenches in order to give room to the long roots of these trees, and often indeed these trenches must also be drained, as is done for olive trees. The conclusion evidently is that it is better to confine ourselves to hydraulic methods of promoting the health fulness of a locality, the immediate effects of which are less uncertain. And then, when the local conditions are such as to make it desirable to try the effects of plants possessed of strongly absorbing powers, it is better to choose them from among the flora of our own hemisphere. This is more sure, and will cost less.
Simple hydraulic methods of purification, even the most perfect, do not, however, produce permanent hygienic effects, since the moisture necessary for the multiplication of the malaria in the soil is so slight that these effects may be compromised by anything whatever that is capable of restoring a moderate degree of humidity to the ground during the hot season. It has often been thought that a suspension of malarial production would be better assured by suppressing at the same time the humidity of the soil and the direct action of the oxygen of the air upon the superficial strata of earth which contain the ferment. This has been successfully accomplished by the system of overlaying (_comblees_). This consists in covering the infected soil by thick layers of uninfected earth, carried there either by the muddy waters of rivers or by the hand of man. At the same time the steady drainage of the surface and underground water is provided for. Last year I advised our Minister of War to undertake in another form a hydraulico-atmospheric purification of the district of the Janiculum surrounding the Salviati Palace on the Via della Longara, by draining the soil carefully and covering with a layer of very close turf all the parts of the surface which could not be macadamized. It would seem as if this system had been rather successful, since there has not been this year a single case of fever in the _personnel_ of the new military college, established in the Salviati Palace; while in the Corsimi Palace, which is situated on the same side of the Via della Longara, but which looks out upon that part of the Janiculum which is still uncovered, there have been some fatal cases of fever.
Furthermore, we have had in Rome, during the past few years, some very evident proofs of the efficacy of atmospheric methods of purification. I will confine myself to the relation here only of the most striking instance, one which has been furnished us in the building up of new quarters of the city. There was much discussion at first as to whether the improvements should be undertaken in the parts where they now are or in the valley of the Tiber, for the uncovered lands of the Esquiline and of the Quirinal were malarious, and, as nearly everybody then thought that the malaria of Rome was carried into the city from the coast marshes, it was supposed that this state of things was irremediable. We opposed to this view the fact of the salubrity of the Viminal, which is situated between the Esquiline and the Quirinal, and which ought to be as unhealthy as the two other hills were the malaria of the latter imported into the city instead of being indigenous. Believing it to be indigenous, we hoped that by shielding the surface of these hills from the direct action of the air (by building houses and paving the streets), the malaria would cease to be produced there. That is precisely what has happened, for the new quarters are very healthy. But the malaria is only held in abeyance, and is not definitely overcome; for if an extensive excavation is made in these hills, and the contact of the air with the malarious soil is thus re-established, during a hot and damp season, the production of malaria commences anew. A complete atmospheric purification is nevertheless the most stable of all the methods of obtaining a suspension of malarial production, but unfortunately its realization is very limited, for it is restricted to inhabited localities and to sodded surfaces.
The ideal method of insuring freedom from malaria should be to obtain a permanent immunity, that is, to be able to modify the composition of the infected soil in such a way as to make it sterile as regards malaria, without taking from it the power of furnishing products useful for the social economy. But all the elements indispensable for obtaining such a result fail us utterly just here. We do not yet know what ought to be, in general terms, the composition of a soil incapable of producing malaria, yet retaining those properties which are suitable for vegetation. When we shall have arrived at this first stage, there will still be a long road to travel; and the most difficult part will be to discover a practical means of imparting this salutary composition to all the numerous varieties of malarious soils.
Scientifically, then, in the present state of our knowledge we are unable to affirm anything on this point. Practically, we are not much further advanced. It is very probable that the combination of hydraulic purification with a forced cultivation of the soil has sometimes determined changes in its composition by which it has been rendered sterile as regards malaria. If that has happened, it has happened by chance, and we are unable to reproduce the result at will; for we have not all the data which might enable us to understand how it has come about. Most of the purifications obtained in ancient times, by means of forced cultivation, continued during centuries, have not been definite at all, but the production of malaria has been simply suspended. Hardly was the regular cultivation of the fields interrupted than the production of malaria recommenced. Among the numerous examples that I might cite in this connection, I will limit myself to that of the Roman Campagna. This seemed to have been made permanently healthy under the Antonii, but after the fall of the empire it began again to produce malaria, as if the forced cultivation through so many centuries had never been.
One might, strictly speaking, be content with such a result, and boldly undertake forced cultivation of all malarious districts, without stopping to ascertain whether the freedom from malaria so obtained would be definite, or whether the production of the poison were only suspended. Unfortunately, one is never sure of arriving at such a result, and no one can say, _a priori_, whether the forced cultivation of a given malarious tract will render it healthful. It must always be remembered that the first effect of forced cultivation, which requires an overturning of the soil by means of the plow, the spade, and the pick, is an unfortunate one, from a hygienic point of view, whenever we have to deal with a malarious country. Experience has shown, especially in Italy and America, that this overturning of the soil almost invariably increases the local production of malaria. And this can be readily understood, since the plowing and the digging in a soil containing the specific ferment increase the extent of surface of the ground in immediate contact with the atmosphere. This first mischievous effect is often gradually weakened by the continued cultivation, and may end by disappearing. At other times, on the contrary, it persists obstinately, and one is often forced in desperation to the resolve to level the ground again and to varnish it, so to speak, with a thick sowing of grass, if he wishes to suspend or weaken the malarial production.
However, when the local conditions will permit, it is well to try whether, by means of forced cultivation of the soil, it may not be possible to increase the efficacy of the hydraulic method of procuring immunity from malaria, or of the hydraulico-atmospheric method of “overlaying.” The moment that it is known that this cultivation has frequently been advantageous, there comes forward a crowd of social reasons which induce us to attempt it, even though we be persuaded that we are about to engage in a game of chance. But to dare to attempt it is not all that is necessary; we need also the possibility of so doing, and just here we find ourselves in a vicious circle from which it is not easy to emerge. Forced cultivation cannot be accomplished without the presence of agriculturists in the region during the entire year; and the agriculturists cannot remain in the region during the fever season, for they run thereby too great a risk. For the solution of this question there is but one means: _try to increase the power of resistance of the human organism to the attacks of the malaria_. It is to a search after the means of accomplishing this result that I have devoted myself during the past few years.
There is nothing to hope for, as regards malaria, in acclimation. _Individual acclimation_ is, and always has been, impossible. The malarial infection is not one of those a first attack of which confers immunity from other attacks. It is, on the contrary, a progressive infection, the duration of which is indeterminate, and which is of such a nature that a single attack may suffice to ruin the constitution for life. Collective or _racial acclimation_ certainly existed in the past, at a time when specific remedies for pernicious malaria were unknown; and even later, when the employment of these remedies was very limited. The acclimation was due to a natural selection made by the malaria upon successive generations, from which it took away, almost without opposition, all those who possessed but a feeble individual power of resistance to the specific poison, while it spared those who possessed this power of resistance in an extraordinary degree. The first were, according to the Grecian myth, _the human victims destined to appease the monster or demon who opposed the violation of the territory over which he had up to that time exercised an absolute sovereignty_. The second became the founders of the race, and through them, from generation to generation, the collective power of resistance to the malaria was progressively increased. In our own days a like selection may take place among barbarous races, as it does among the cattle and the horses in a malarious region, but it has become an impossibility among civilized nations. By means of the specific remedies which we possess, the use of which is now so general, the lives of a large number of individuals whose resisting powers are very feeble are preserved; and these individuals beget others whose power of resistance to the action of the specific poison is still more feeble. This results after a number of generations in the physical degradation of that part of the human race which inhabits malarious countries.
We cannot, therefore, in the future, count upon the assistance of external natural forces to increase the power of resistance of human society against the assaults of malaria. Such an object can be obtained only by artificial means. It has been sought to attain this end by the daily administration of the salts of quinine, of the salicylates, and of the tincture of eucalyptus, each and every one tried in turn. But the salts of quinine are dear, exercise a prompt, though very transient anti-malarial action, and, when administered for a long time, disturb rather seriously the functions of the digestive and nervous systems. The salicylates, when well prepared, are rather dear, and there is as yet no proof that they possess prophylactic powers against malaria. The alcoholic tincture of eucalyptus is useful in malarious regions (as are all the alcoholics, beginning with wine) in quickening the circulation of the blood; may it, perhaps, also act as a preservative against light attacks of malaria? Possibly. But it is very certain that it possesses no efficacy in places where malaria is severe. It will suffice to prove this to recall the two epidemics of fever which afflicted the colony of the Tre Fontaine, near Rome, in 1880 and 1882. Everybody was attacked, and there were several cases of pernicious fever, although a good preparation of eucalyptus is manufactured in the place and is distributed largely to the colonists during the dangerous season of the year.
ARSENIC FOR MALARIA.
Having several times had occasion to observe, in malarious regions, that when recourse was had to arsenic in order to subdue fevers over which quinine had exerted almost no effect, relapses occurred but rarely; and having been able to satisfy myself that the arsenical treatment sometimes procured a permanent, immunity in individuals who are subject to frequent attacks of malaria, I began in 1880 to employ arsenic (arsenious acid) as a prophylactic in certain portions of the Roman Campagna. This remedy was indicated in an experiment of this sort, not only by reason of its durable anti-malarialae effects, but also by its low price, by the beneficial influence it exerts upon all the nutritive functions, and because it has no disagreeable taste and may therefore be given to everybody, even to children. My first trials in 1880 were rather encouraging, and I felt myself justified in engaging some proprietors and the association of our southern railroads to repeat the experiments on a large scale the following year, recommending them, however, to use arsenic in a solid form as offering an easy and certain dosage. This extensive prophylactic experiment began in 1881, and acquired constantly increasing proportions in 1882 and 1883, which have become still larger this year. An experiment of this kind is not easy to conduct in the beginning. The name, arsenic, frightens not only those whom we desire to submit to its action, but also the physicians, whose exaggerated fears have sometimes rendered the experiments of no avail, since they were conducted too timidly and the doses of arsenic employed were altogether insufficient. But some intelligent men, especially M. Ricchi, physician in chief to the southern railroads, were able speedily to triumph over these obstacles, and to place the experiment on a firm basis. The general testimony of all the facts which they have collected tends really to prove that when the administration of arsenic is begun some weeks before the presumed season for the appearance of the fever, and when it is continued regularly throughout the whole of this season, the power of resistance of the human organism to malaria is increased. Many individuals gained thereby a complete immunity, others a partial immunity, that is to say, they were sometimes attacked by the fever, but it never, even in very malarious districts, assumed a pernicious form, and was easily subdued by very moderate doses of quinine. Last year, for example, in the district of Borino, where the malaria is very severe, M. Ricchi experimented upon seventy-eight employes of the southern railroads, dividing them into two equal divisions, one of which received no prophylactic treatment, while the other was submitted to a systematic arsenical treatment. At the end of the fever season it was found that several employes among the first half had been attacked by fevers of a severe type; while thirty-six of those in the second division had enjoyed a complete immunity, the three others having been attacked, but so lightly that they cured themselves by quinine without seeking medical aid.
Facts of this sort are very encouraging, and the more so as the general health of those submitted to the prophylactic treatment was much improved. It was found almost invariably, upon the termination of the experiment, that there had been an increase in bodily weight and an amelioration of the anaemia which is so common in milarious districts. But, in order to arrive at such results, it is necessary to be at once bold and prudent. On the one hand, it is necessary to graduate very carefully the daily dose, never exceeding at the commencement the dose of two milligrammes (3/100 grain per diem) for adults, and never giving the arsenic upon an empty stomach. On the other hand, it is necessary to gradually push the dose up to ten or twelve milligrammes (15/100 or 18/100) a day for adults, in districts where the malaria is very severe, giving the arsenic in such a way that there is never an accumulation of the drug in the stomach. Most of the experiments which have been undertaken this year are being conducted on this plan, and there is reason to hope that they will give satisfactory results.
We must not, however, rest here if we wish to attain promptly the end proposed, namely, that of planting colonies in malarious districts without exposing the colonists to grave danger. Even if we realize perfectly the hope which I conceived in 1880, and if we are enabled to prove that arsenic increases man’s power of resistance to the assaults of malaria, we must not imagine that everything is accomplished. It will take a long time before the use of a preservative method of this kind becomes generalized; we have first to contend against the fear which nearly every one experiences when arsenic is mentioned, and then there will also be difficulty in establishing everywhere a proper control over its administration. In every attempt at the colonization of malarious regions it will be necessary to combat for a long time the diseases caused by malaria, and we must seek for a method of combating them by a means which is in the possession of everybody, and which shall not be dangerous to the general economy of the human organism. Those who do not know from actual experience the miseries of a malarious country, think only of combating the acute forms of infection, which often place the patient in danger of death. But this danger, though great, is for the most part imaginary, provided that assistance be obtained in time. But that which desolates families, and which causes a physical degradation of the human race exposed to the attacks of malaria, is the chronic poisoning, which undermines the springs of life and produces a slow but progressive anaemia. This infection often resists all human therapeutic measures, and is even aggravated by the use of quinine, which is given during the recurrent paroxysms of fever. Quinine is, when given for a long period of time, a true poison to the vaso-motor nerves. The question, then, is to replace quinine, and the alkaloids which possess an analogous physiological action, by an agent the efficacy of which against, chronic malarial poisoning may be greater and the dangers of its employment less.
THE LEMON FOR MALARIA.
A happy chance has led Dr. Magliori to the discovery of an agent of this sort which was traditionally in use by certain Italian families. It is an exceedingly simple thing–merely a decoction of lemon. It is prepared by cutting up one lemon, peel and all, into thin slices, which are then put into three glassfuls of water and the whole boiled down to one glassful. It is then strained through linen, squeezing the remains of the boiled lemon, and set aside for some hours to cool. The whole amount of the liquid is then taken fasting. It is well known that in Italy, Greece, and North Africa, they often use lemon juice or a decoction of lemon seeds, as a remedy in malarial fevers of moderate intensity; and in Guadaloupe they use for the same purpose a decoction of the bark of the roots of the lemon tree. All these popular practices tend to show that the lemon tree produces a febrifuge substance, which resides in all parts of the plant, but which would seem to be most abundant in the fruit. In fact, among the popular remedies employed against malarial infection, that which I have just described is the most efficacious, for it can be employed with good effects in acute fevers. But it is especially advantageous in combating the chronic infection, which is rebellious to the action of quinine, and in removing or moderating its deplorable effects.
Hardly had I learned of this method of medication, when I hastened to induce some proprietors in the Roman Campagna to try it with their farm hands; and, after witnessing the good results there, I endeavored to persuade practitioners to make a trial of the same treatment. I was ridiculed a little at first, for they thought it rather singular that a professor should be trying to popularize on old woman’s remedy. In reply to that I answered that practical medicine would not have existed, had it not known how to treasure up from age to age the facts of popular experience; and I ventured to remark that, had the Countess de Chinchon waited until methodical researches had been made into the physiological action of cinchona bark, before popularizing the remedy, the use of which she had learned from the semi-barbarous Peruvians, in all probability humanity would still, as regards malaria, be dependent upon the medication practiced in the middle ages. Happily these arguments had the desired effect upon certain distinguished practitioners, some of whom, especially in Sicily and Tuscany, have already collected together a tolerably large number of very encouraging observations. One of them, Dr. Mascagni, of Avezzo, tried the remedy in his own person, and succeeded in promptly curing an obstinate malarial fever which had resisted the action of quinine.
Gentlemen, in dealing with malaria we ought always to hold popular experience in high esteem, for we owe much to it. We owe to it the fact that we have been liberated from the paludal idea, and furthermore, that we have learned that it is often better, instead of trying to prevent the importation, for the most part imaginary, of malaria from distant marshes, to suppress its production in the soil under our feet or in that immediately surrounding us. We owe to it the knowledge, which we now have, that malaria rises up into the atmosphere only to a limited height, so that by placing ourselves a little above this limit in order to eliminate the possibility of the malaria being carried up to us by oblique atmospheric currents, we are enabled to breathe an air which does not contain this ferment, or which contains it only in insignificant amounts; thus one may even sleep in the open air during the night in very unhealthy districts without running any risks. The knowledge of this fact has led some peoples of Greece, and the inhabitants of the Pontine Marshes, to sleep in the open air on platforms raised on poles four or five meters (twelve to fifteen feet) in height. Some people in the Roman Campagna have built houses for themselves on top of the ancient tombs, the walls of which are perpendicular; the American Indians fasten their hammocks as high up as possible to the trees of the malarious forests; and very recently, the engineers of the Panama Railroad had little wooden huts built in the trees in order to procure safety against the terrible outbreak of malaria which occurred during the construction of that iron way. We owe, finally, to this popular experience the discovery of the specific action of quinine, and the consequent preservation of thousands and thousands of human lives. Why should we reject _a priori_ and without investigation other useful data which it may yet present to our consideration? If we wish to make progress in this question of rendering malarious countries healthy, we must always hold before our eyes a double object–to find a means of prophylaxis which may be accessible to everybody; and, at the same time, to find a means equally within everybody’s reach, to overcome chronic malarial poisoning and its evil consequences. Science is still too far behind to permit us to hope that we shall soon succeed in discovering this second means by purely scientific researches. We ought, therefore, to gather together with great care all the facts which point to the possibility of a solution of this problem, and if the measures to which these facts point seem to be incapable of doing harm, we ought to try them boldly, and not be restrained by a false idea of the dignity of science. The social importance of the problem is too great to allow of its solution being retarded by the fear that scientific men may be accused of having been outrun by the ignorant. True science has none of these puerile susceptibilities; on the contrary, it deems it an honor to be able to seize all the observations of fact, whoever may have been their first recorder, to put them to the crucial test of methodical experiment, and to convert them into a new stepping stone on the march of human progress.
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HALESIA HISPIDA.
[Illustration: HALESIA HISPIDA: HARDY SHRUB: FLOWERS WHITE.]
This fine hardy shrub is perhaps best known under the name of Pterostyrax, but we think gardeners will, quite independently of botanical grounds, be inclined to thank Messrs. Bentham and Hooker for reducing the genus to the more easily remembered name of Halesia. Halesia hispida is a hardy Japanese shrub of recent introduction, with numerous white Deutzia-like flowers in long terminal racemes. A peculiar appearance is produced by the arrangement of the flowers on one side only of the branchlets of the inflorescence. The botanical history of the plant is well known, and our illustration is sufficient to show the general appearance of the plant. It is decidedly one of the best recent additions to the number of hardy deciduous flowering shrubs. For the specimen whence our figure was taken we are indebted to W.E. Gumbleton, Esq.–_The Gardeners’ Chronicle_.
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WINDFLOWERS.
[Illustration: FLOWERS OF ANEMONE DECAPETALA (Natural Size).]