this telephone is that its regulation is permanent. Besides this, it possesses remarkable power and clearness, and is accompanied with no snuffling sounds, a fact doubtless owing to all the molecules of the disk being immersed in the magnetic field, and to the actions of the two poles occurring concentrically with the disk. As we have above said, this apparatus is beginning to be appreciated, and has already been the object of several applications in the army. The transmitter is used by the artillery service in the organization of observatories from which to watch firing, and the receiver is added to the apparatus pertaining to military telegraphy. The two small receivers are held to the lens of the operator by the latter’s hat strap, while the transmitter is suspended in a case supported by straps, with the mouthpieces near the face (Fig. 1).
In the figure, the case is represented as open, so as to show the transmitter. The empty compartment below is designed for the reception and carriage of the receivers, straps, and flexible cords. This arrangement permits of calling without the aid of special apparatus, and it has also the advantage of giving entire freedom to the man on observation, this being something that is indispensable in a large number of cases.
[Illustration: FIG. 3.–RECEIVER TAKEN APART.]
In certain applications, of course, the receivers may be combined with a microphone; yet on an aerial as well as on a subterranean line the transmitter produces effects which, as regards intensity and clearness, are comparable with those of a pile transmitter.
Stations wholly magnetic may be established by adding to the transmitter and two receivers a Sieur phonic call, which will actuate them powerfully, and cause them to produce a noise loud enough for a call. It would be interesting to try this telephone on a city line, and to a great distance on those telegraph lines that are provided with the Van Rysselberghe system. Excellent results would certainly be obtained, for, as we have recently been enabled to ascertain, the voice has a remarkable intensity in this telephone, while at the same time perfectly preserving its quality.–_La Nature_.
* * * * *
[NATURE.]
THE MELDOMETER.
The apparatus which I propose to call by the above name ([mu][epsilon][lambda][delta][omega], to melt) consists of an adjunct to the mineralogical microscope, whereby the melting-points of minerals may be compared or approximately determined and their behavior watched at high temperatures either alone or in the presence of reagents.
As I now use it, it consists of a narrow ribbon of platinum (2 mm. wide) arranged to traverse the field of the microscope. The ribbon, clamped in two brass clamps so as to be readily renewable, passes bridgewise over a little scooped-out hollow in a disk of ebony (4 cm. diam.). The clamps also take wires from a battery (3 Groves cells); and an adjustable resistance being placed in circuit, the strip can be thus raised in temperature up to the melting-point of platinum.
The disk being placed on the stage of the microscope the platinum strip is brought into the field of a 1″ objective, protected by a glass slip from the radiant heat. The observer is sheltered from the intense light at high temperatures by a wedge of tinted glass, which further can be used in photometrically estimating the temperature by using it to obtain extinction of the field. Once for all approximate estimations of the temperature of the field might be made in terms of the resistance of the platinum strip, the variation of such resistance with rise of temperature being known. Such observations being made on a suitably protected strip might be compared with the wedge readings, the latter being then used for ready determinations. Want of time has hindered me from making such observations up to this.
The mineral to be experimented on is placed in small fragments near the center of the platinum ribbon, and closely watched while the current is increased, till the melting-point of the substance is apparent. Up to the present I have only used it comparatively, laying fragments of different fusibilities near the specimen. In this way I have melted beryl, orthoclase, and quartz. I was much surprised to find the last mineral melt below the melting-point of platinum. I have, however, by me as I write, a fragment, formerly clear rock-crystal, so completely fused that between crossed Nicols it behaves as if an amorphous body, save in the very center where a speck of flashing color reveals the remains of molecular symmetry. Bubbles have formed in the surrounding glass.
Orthoclase becomes a clear glass filled with bubbles: at a lower temperature beryl behaves in the same way.
Topaz whitens to a milky glass–apparently decomposing, throwing out filmy threads of clear glass and bubbles of glass which break, liberating a gas (fluorine?) which, attacking the white-hot platinum, causes rings of color to appear round the specimen. I have now been using the apparatus for nearly a month, and in its earliest days it led me right in the diagnosis of a microscopical mineral, iolite, not before found in our Irish granite, I think. The unlooked-for characters of the mineral, coupled with the extreme minuteness of the crystals, led me previously astray, until my meldometer fixed its fusibility for me as far above the suspected bodies.
Carbon slips were at first used, as I was unaware of the capabilities of platinum.
A form of the apparatus adapted, at Prof. Fitzgerald’s suggestion, to fit into the lantern for projection on the screen has been made for me by Yeates. In this form the heated conductor passes both below and above the specimen, which is regarded from a horizontal direction.
J. JOLY.
Physical Laboratory, Trinity College, Dublin.
* * * * *
[AMERICAN ANNALS OF THE DEAF AND DUMB.]
TOUCH TRANSMISSION BY ELECTRICITY IN THE EDUCATION OF DEAF-MUTES.
Progress in electrical science is daily causing the world to open its eyes in wonder and the scientist to enlarge his hopes for yet greater achievements. The practical uses to which this subtile fluid, electricity, is being put are causing changes to be made in time-tested methods of doing things in domestic, scientific, and business circles, and the time has passed when startling propositions to accomplish this or that by the assistance of electricity are dismissed with incredulous smiles. This being the case, no surprise need follow the announcement of a device to facilitate the imparting of instruction to deaf children which calls into requisition some service from electricity.
The sense of touch is the direct medium contemplated, and it is intended to convey, with accuracy and rapidity, messages from the operator (the teacher) to the whole class simultaneously by electrical transmission.[1]
[Footnote 1: By the same means two deaf-mutes, miles apart, might converse with each other, and the greatest difficulty in the way of a deaf-mute becoming a telegraph operator, that of receiving messages, would be removed. The latter possibilities are incidentally mentioned merely as of scientific interest, and not because of their immediate practical value. The first mentioned use to which the device may be applied is the one considered by the writer as possibly of practical value, the consideration of which suggested the appliance to him.]
An alphabet is formed upon the palm of the left hand and the inner side of the fingers, as shown by the accompanying cut, which, to those becoming familiar with it, requires but a touch upon a certain point of the hand to indicate a certain letter of the alphabet.
A rapid succession of touches upon various points of the hand is all that is necessary in spelling a sentence. The left hand is the one upon which the imaginary alphabet is formed, merely to leave the right hand free to operate without change of position when two persons only are conversing face to face.
The formation of the alphabet here figured is on the same principle as one invented by George Dalgarno, a Scottish schoolmaster, in the year 1680, a cut of which maybe seen on page 19 of vol. ix. of the _Annals_, accompanying the reprint of a work entitled “_Didascalocophus_.” Dalgarno’s idea could only have been an alphabet to be used in conversation between two persons _tete a tete_, and–except to a limited extent in the Horace Mann School and in Professor Bell’s teaching–has not come into service in the instruction of deaf-mutes or as a means of conversation. There seems to have been no special design or system in the arrangement of the alphabet into groups of letters oftenest appearing together, and in several instances the proximity would seriously interfere with distinct spelling; for instance, the group “u,” “y,” “g,” is formed upon the extreme joint of the little finger. The slight discoverable system that seems to attach to his arrangement of the letters is the placing of the vowels in order upon the points of the fingers successively, beginning with the thumb, intended, as we suppose, to be of mnemonic assistance to the learner. Such assistance is hardly necessary, as a pupil will learn one arrangement about as rapidly as another. If any arrangement has advantage over another, we consider it the one which has so grouped the letters as to admit of an increased rapidity of manipulation. The arrangement of the above alphabet, it is believed, does admit of this. Yet it is not claimed that it is as perfect as the test of actual use may yet make it. Improvements in the arrangement will, doubtless, suggest themselves, when the alterations can be made with little need of affecting the principle.
In order to transmit a message by this alphabet, the following described appliance is suggested: A matrix of cast iron, or made of any suitable material, into which the person receiving the message (the pupil) places his left hand, palm down, is fixed to the table or desk. The matrix, fitting the hand, has twenty-six holes in it, corresponding in position to the points upon the hand assigned to the different letters of the alphabet. In these holes are small styles, or sharp points, which are so placed as but slightly to touch the hand. Connected with each style is a short line of wire, the other end of which is connected with a principal wire leading to the desk of the operator (the teacher), and there so arranged as to admit of opening and closing the circuit of an electric current at will by the simple touch of a button, and thereby producing along the line of that particular wire simultaneous electric impulses, intended to act mechanically upon all the styles connected with it. By these impulses, produced by the will of the sender, the styles are driven upward with a quick motion, but with only sufficient force to be felt and located upon the hand by the recipient. Twenty-six of these principal or primary wires are run from the teacher’s desk (there connected with as many buttons) under the floor along the line of pupils’ desks. From each matrix upon the desk run twenty-six secondary wires down to and severally connecting with the twenty-six primary wires under the floor. The whole system of wires is incased so as to be out of sight and possibility of contact with foreign substances. The keys or buttons upon the desk of the teacher are systematically arranged, somewhat after the order of those of the type writer, which allows the use of either one or both hands of the operator, and of the greatest attainable speed in manipulation. The buttons are labeled “a,” “b,” “c,” etc., to “z,” and an electric current over the primary wire running from a certain button (say the one labeled “a”) affects only those secondary wires connected with the styles that, when excited, produce upon the particular spot of the hands of the receivers the tactile impression to be interpreted as “a.” And so, whenever the sender touches any of the buttons on his desk, immediately each member of the class feels upon the palm of his hand the impression meant to be conveyed. The contrivance will admit of being operated with as great rapidity as it is probable human dexterity could achieve, i.e., as the strokes of an electric bell. It was first thought of conveying the impressions directly by slight electric shocks, without the intervention of further mechanical apparatus, but owing to a doubt as to the physical effect that might be produced upon the persons receiving, and as to whether the nerves might not in time become partly paralyzed or so inured to the effect as to require a stronger and stronger current, that idea was abandoned, and the one described adopted. A diagram of the apparatus was submitted to a skillful electrical engineer and machinist of Hartford, who gave as his opinion that the scheme was entirely feasible, and that a simple and comparatively inexpensive mechanism would produce the desired result.
[Illustration: TOUCH TRANSMISSION BY ELECTRICITY.]
The matter now to consider, and the one of greater interest to the teacher of deaf children, is, Of what utility can the device be in the instruction of deaf-mutes? What advantage is there, not found in the prevailing methods of communication with the deaf, i.e., by gestures, dactylology, speech and speech-reading, and writing?
I. The language of gestures, first systematized and applied to the conveying of ideas to the deaf by the Abbe de l’Epee during the latter part of the last century, has been, in America, so developed and improved upon by Gallaudet, Peet, and their successors, as to leave but little else to be desired for the purpose for which it was intended. The rapidity and ease with which ideas can be expressed and understood by this “language” will never cease to be interesting and wonderful, and its value to the deaf can never fail of being appreciated by those familiar with it. But the genius of the language of signs is such as to be in itself of very little, if any, direct assistance in the acquisition of syntactical language, owing to the diversity in the order of construction existing between the English language and the language of signs. Sundry attempts have been made to enforce upon the sign-language conformity to the English order, but they have, in all cases known to the writer, been attended with failure. The sign-language is as immovable as the English order, and in this instance certainly Mahomet and the mountain will never know what it is to be in each other’s embrace. School exercises in language composition are given with great success upon the basis of the sign-language. But in all such exercises there must be a translation from one language to the other. The desideratum still exists of an increased percentage of pupils leaving our schools for the deaf, possessing a facility of expression in English vernacular. This want has been long felt, and endeavoring to find a reason for the confessedly low percentage, the sign-language has been too often unjustly accused. It is only when the sign-language is abused that its merit as a means of instruction degenerates. The most ardent admirers of a proper use of signs are free to admit that any excessive use by the pupils, which takes away all opportunities to express themselves in English, is detrimental to rapid progress in English expression.
II. To the general public, dactylology or finger spelling is the sign-language, or the basis of that language, but to the profession there is no relation between the two methods of communication. Dactylology has the advantage of putting language before the eye in conformity with English syntax, and it has always held its place as one of the elements of the American or eclectic method. This advantage, however, is not of so great importance as to outweigh the disadvantages when, as has honestly been attempted, it asserts its independence of other methods. Very few persons indeed, even after long practice, become sufficiently skillful in spelling on the fingers to approximate the rapidity of speech. But were it possible for all to become rapid spellers, another very important requisite is necessary before the system could be a perfect one, that is, the ability to _read_ rapid spelling. The number of persons capable of reading the fingers beyond a moderate degree of rapidity is still less than the number able to spell rapidly. While it is physically possible to follow rapid spelling for twenty or thirty minutes, it can scarcely be followed longer than that. So long as this is true, dactylology can hardly claim to be more than one of the _elements_ of a system of instruction for the deaf.
III. Articulate speech is another of the elements of the eclectic method, employed with success inversely commensurate with the degree of deficiency arising from deafness. Where the English order is already fixed in his mind, and he has at an early period of life habitually used it, there is comparatively little difficulty in instructing the deaf child by speech, especially if he have a quick eye and bright intellect. But the number so favored is a small percentage of the great body of deaf-mutes whom we are called upon to educate. When it is used as a _sole_ means of educating the deaf as a class its inability to stand alone is as painfully evident as that of any of the other component parts of the system. It would seem even less practicable than a sole reliance upon dactylology would be, for there can be no doubt as to what a word is if spelled slowly enough, and if its meaning has been learned. This cannot be said of speech. Between many words there is not, when uttered, the slightest visible distinction. Between a greater number of others the distinction is so slight as to cause an exceedingly nervous hesitation before a guess can be given. Too great an imposition is put upon the eye to expect it to follow unaided the extremely circumscribed gestures of the organs of speech visible in ordinary speaking. The ear is perfection as an interpreter of speech to the brain. It cannot correctly be said that it is _more_ than perfection. It is known that the ear, in the interpretation of vocal sounds, is capable of distinguishing as many as thirty-five sounds per second (and oftentimes more), and to follow a speaker speaking at the rate of more than two hundred words per minute. If this be perfection, can we expect the _eye_ of ordinary mortal to reach it? Is there wonder that the task is a discouraging one for the deaf child?
But it has been asserted that while a large percentage (practically all) of the deaf _can_, by a great amount of painstaking and practice, become speech readers in some small degree, a relative degree of facility in articulation is not nearly so attainable. As to the accuracy of this view, the writer cannot venture an opinion. Judging from the average congenital deaf-mute who has had special instruction in speech, it can safely be asserted that their speech is laborious, and far, very far, from being accurate enough for practical use beyond a limited number of common expressions. This being the case, it is not surprising that as an unaided means of instruction it cannot be a success, for English neither understood when spoken, nor spoken by the pupil, cannot but remain a foreign language, requiring to pass through some other form of translation before it becomes intelligible.
There are the same obstacles in the use of the written or printed word as have been mentioned in connection with dactylology, namely, lack of rapidity in conveying impressions through the medium of the English sentence.
I have thus hastily reviewed the several means which teachers generally are employing to impart the use of English to deaf pupils, for the purpose of showing a common difficulty. The many virtues of each have been left unnoticed, as of no pertinence to this article.
The device suggested at the beginning of this paper, claiming to be nothing more than a school room appliance intended to supplement the existing means for giving a knowledge and practice of English to the deaf, employs as its interpreter a different sense from the one universally used. The sense of sight is the sole dependence of the deaf child. Signs, dactylology, speech reading, and the written and printed word are all dependent upon the eye for their value as educational instruments. It is evident that of the two senses, sight and touch, if but one could be employed, the choice of sight as the one best adapted for the greatest number of purposes is an intelligent one; but, as the choice is not limited, the question arises whether, in recognizing the superior adaptability to our purpose of the one, we do not lose sight of a possibly important, though secondary, function in the other. If sight were all-sufficient, there would be no need of a combination. But it cannot be maintained that such is the case. The plan by which we acquire our vernacular is of divine, and not of human, origin, and the senses designed for special purposes are not interchangeable without loss. The theory that the loss of a certain sense is nearly, if not quite, compensated for by increased acuteness of the remaining ones has been exploded. Such a theory accuses, in substance, the Maker of creating something needless, and is repugnant to the conceptions we have of the Supreme Being. When one sense is absent, the remaining senses, in order to equalize the loss, have imposed upon them an unusual amount of activity, from which arises skill and dexterity, and by which the loss of the other sense is in some measure alleviated, but not supplied. No _additional_ power is given to the eye after the loss of the sense of hearing other than it might have acquired with the same amount of practice while both faculties were active. The fact, however, that the senses, in performing their proper functions, are not overtaxed, and are therefore, in cases of emergency, capable of being extended so as to perform, in various degrees, additional service, is one of the wise providences of God, and to this fact is due the possibility of whatever of success is attained in the work of educating the deaf, as well as the blind.
In the case of the blind, the sense of touch is called into increased activity by the absence of the lost sense; while in the case of the deaf, sight is asked to do this additional service. A blind person’s education is received principally through the _two_ senses of hearing and touch. Neither of these faculties is so sensible to fatigue by excessive use as is the sense of sight, and yet the eye has, in every system of instruction applied to the deaf, been the sole medium. In no case known to the writer, excepting in the celebrated case of Laura Bridgman and a few others laboring under the double affliction of deafness and blindness, has the sense of touch been employed as a means of instruction.[1]
[Footnote 1: This article was written before Professor Bell had made his interesting experiments with his “parents’ class” of a touch alphabet, to be used upon the pupil’s shoulder in connection with the oral teaching.–E.A.F.]
Not taking into account the large percentage of myopes among the deaf, we believe there are other cogent reasons why, if found practicable, the use of the sense of touch may become an important element in our eclectic system of teaching. We should reckon it of considerable importance if it were ascertained that a portion of the same work now performed by the eye could be accomplished equally as well through feeling, thereby relieving the eye of some of its onerous duties.
We see no good reason why such accomplishment may not be wrought. If, perchance, it were discovered that a certain portion could be performed in a more efficient manner, its value would thus be further enhanced.
In theory and practice, the teacher of language to the deaf, by whatever method, endeavors to present to the eye of the child as many completed sentences as are nominally addressed to the ear–having them “caught” by the eye and reproduced with as frequent recurrence as is ordinarily done by the child of normal faculties.
In our hasty review of the methods now in use we noted the inability to approximate this desirable process as a common difficulty. The facility now ordinarily attained in the manipulation of the type writer, and the speed said to have been reached by Professor Bell and a private pupil of his by the Dalgarno touch alphabet, when we consider the possibility of a less complex mechanism in the one case and a more systematic grouping of the alphabet in the other, would lead us to expect a more rapid means of communication than is ordinarily acquired by dactylology, speech (by the deaf), or writing. Then the ability to receive the communication rapidly by the sense of feeling will be far greater. No part of the body except the point of the tongue is as sensible to touch as the tips of the fingers and the palm of the hand. Tactile discrimination is so acute as to be able to interpret to the brain significant impressions produced in very rapid succession. Added to this advantage is the greater one of the absence of any more serious attendant physical or nervous strain than is present when the utterances of speech fall upon the tympanum of the ear. To sum up, then, the advantages of the device we find–
First. A more rapid means of communication with the deaf by syntactic language, admitting of a greater amount of practice similar to that received through the ear by normal children.
Second. Ability to receive this rapid communication for a longer duration and without ocular strain.
Third. Perfect freedom of the eye to watch the expression on the countenance of the sender.
Fourth. In articulation and speech-reading instruction, the power to assist a class without distracting the attention of the eye from the vocal organs of the teacher.
Fifth. Freedom of the right hand of the pupil to make instantaneous reproduction in writing of the matter being received through the sense of feeling, thereby opening the way for a valuable class exercise.
Sixth. The possible mental stimulus that accompanies the mastery of a new language, and the consequent ability to receive known ideas through a new medium.
Seventh. A fresh variety of class exercises made possible.
The writer firmly believes in the good that exists in all methods that are, or are to be; in the interdependence rather than the independence of all methods; and in all school-room appliances tending to supplement or expedite the labors of the teacher, whether they are made of materials delved from the earth or snatched from the clouds.
S. TEFFT WALKER,
_Superintendent of the Kansas Institution, Olathe, Kans_.
* * * * *
WATER GAS.
THE RELATIVE VALUE OF WATER GAS AND OTHER GASES AS IRON REDUCING AGENTS.
By B.H. THWAITE.
In order to approximately ascertain the relative reducing action of water gas, carbon monoxide, and superheated steam on iron ore, the author decided to have carried out the following experiments, which were conducted by Mr. Carl J. Sandahl, of Stockholm, who also carried out the analyses. The ore used was from Bilbao, and known as the Ruby Mine, and was a good average hematite. The carbonaceous material was the Trimsaran South Wales anthracite, and contained about 90 per cent. of carbon.
A small experimental furnace was constructed of the form shown by illustration, about 4 ft. 6 in. high and 2 ft. 3 in. wide at the base, and gradually swelling to 2 ft. 9 in. at the top, built entirely of fireclay bricks. Two refractory tubes, 2 in. square internally, and the height of the furnace, were used for the double purpose of producing the gas and reducing the ore.
The end of the lower tube rested on a fireclay ladle nozzle, and was properly jointed with fireclay; through this nozzle the steam or air was supplied to the inside of the refractory tubes. In each experiment the ore and fuel were raised to the temperature “of from 1,800 to 2,200 deg. Fahr.” by means of an external fire of anthracite. Great care was taken to prevent the contact of the solid carbonaceous fuel with the ore. In each experiment in which steam was used, the latter was supplied at a temperature equivalent to 35 lb. to the square inch.
The air for producing the carbon monoxide (CO) gas was used at the temperature of the atmosphere. As near as possible, the same conditions were obtained in each experiment, and the equivalent weight of air was sent through the carbon to generate the same weight of CO as that generated when steam was used for the production of water gas.
[Illustration]
_First Experiment, Steam (per se)_.–Both tubes, A and B, were filled with ore broken to the size of nuts. The tube, A, was heated to about 2,000 deg. Fahr., the upper one to about 1,500 deg.
NOTE.–In this experiment, part of the steam was dissociated in passing through the turned-up end of the steam supply pipe, which became very hot, and the steam would form with the iron the magnetic oxide (Fe_{3}O_{4}). The reduction would doubtless be due to this dissociation. The pieces of ore found on lowest end of the tube, A, were dark colored and semi-fused; part of one of these pieces was crushed fine, and tested; see column I. The remainder of these black pieces was mixed with the rest of the ore contained in tube, A, and ground and tested; see column II. The ore in upper tube was all broken up together and tested; see column III. When finely crushed, the color of No. I. was bluish black; No. II., a shade darker red; No. III., a little darker than the natural color of the ore. The analyses gave:
—————————–+———+———+——— | I. | II. | III.
+———+———+——— |per cent.|per cent.|per cent. Ferric oxide (Fe_{2}O_{3}). | 68.55 | 76.47 | 84.81 Ferrous oxide (FeO). | 16.20 | 9.50 | 1.50 +———+———+——— Total. | 84.75 | 85.97 | 86.31 +———+———+——— Calculated: | | |
Ferric oxide (Fe_{2}O_{3}). | 32.55 | 55.36 | 81.47 Magnetic oxide (Fe_{3}O_{4}).| 52.20 | 30.61 | 4.84 Ferrous oxide (FeO). | | |
+———+———+——— Total. | 84.75 | 85.97 | 86.31 +———+———+——— Percentage of total
oxygen reduced. | 6.93 | 4.02 | 1.07 Metallic iron. | 60.59 | 60.92 | 60.54 —————————–+———+———+———
_Second Experiment, Water Gas_.–The tube, A, was filled with small pieces of anthracite, and heated until all the volatile matter had been expelled. The tube, B, was then placed in tube, A, the joint being made with fireclay, and to prevent the steam from carrying small particles of solid carbon into ore in the upper tube, the anthracite was divided from the ore by means of a piece of fine wire gauze. The steam at a pressure of about 35 lb. to the square inch was passed through the anthracite. The tube, A, was heated to white heat, the tube, B, at its lower end to bright red, the top to cherry red.
——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+ Experiment. | 1st. | 2d. | 3d. | ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+ Number. | I. | II. | III.| I. | II. | III.| IV. | I. | II. | III.| ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+ Total Iron. |60.59|60.92|60.54|65.24|61.71|61.93|57.23|59.73|57.93|55.54| ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+
Iron occurring as
——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+ FeO. |12.60| 7.39| 1.17|46.98|18.59| 4.03| 0.84|29.45| 2.69| 1.12 Fe_{2}O_{3} |47.99|53.33|59.37|18.26|43.12|57.90|56.39|30.28|55.24|54.42 ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+
Per cent. of Oxides. | ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+ FeO. |16.20| 9.50| 1.50|60.40|23.90| 5.18| 1.08|37.86| 3.46| 1.44 Fe_{2}O_{3}. |68.55|76.47|84.81|26.08|61.60|82.71|80.55|43.26|78.91|77.74 Total. |84.75|85.97|86.31|86.48|85.50|87.89|81.63|81.12|82.37|79.18 ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+
Oxygen in Ore.
——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+ Before experiment.|25.97|26.10|26.05|27.96|26.45|26.54|24.52|25.60|24.81|23.80 After experiment. |24.16|25.05|25.77|21.24|23.79|25.96|24.40|21.39|24.44|23.64 Difference. | 1.81| 1.05| 0.28| 6.72| 2.66| 0.58| 0.12| 4.21| 0.37| 0.16 ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+
Per cent. of oxygen reduced.
——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+ oxygen reduced. | 6.93| 4.02| 1.07|24.03|10.02| 2.18| 0.49|16.44| 1.49| 0.42 ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+
Degree of Oxidation of the Ore after the Experiment. ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+ FeO. | … | … | … |84.66| … | … | … |18.40| … | … | Fe_{3}O_{4}. |52.20|30.61| 4.84|37.82|77.01|28.12| 3.88|62.72|11.14| 4.64| Fe_{2}O_{3}. |32.55|55.36|81.47| … | 8.49|59.77|77.75| … |71.23|74.54| Total. |84.75|85.97|85.97|85.97|85.97|85.97|85.97|85.97|85.97|85.97| ——————+—–+—–+—–+—–+—–+—–+—–+—–+—–+—–+
——————+—————–+———————–+—————–+ The ore having | | | | been exposed to | Steam. | Water gas. | Carbon monoxide.| ——————+—————–+———————–+—————–+
_Four Samples were Tested_.–I. The bottom layer, 11/4 in. thick; the color of ore quite black, with small particles of reduced spongy metallic iron. II. Layer above I., 41/4 in. thick; the color was also black, but showed a little purple tint. III. Layer above II., 5 in. thick; purple red color. IV. Layer above III., ore a red color. The analyses gave:
—————————–+———+———+———+——— | I. | II. | III. | IV. +———+———+———+——— |per cent.|per cent.|per cent.|per cent. Ferric oxide (Fe_{2}O_{3}). | 26.08 | 61.60 | 82.71 | 80.55 Ferrous oxide (FeO). | 60.40 | 23.90 | 5.18 | 1.08 +———+———+———+——— Total. | 86.48 | 85.50 | 87.89 | 81.63 +———+———+———+——— Calculated: | | | |
Ferric oxide (Fe_{2}O_{3}). | … | 8.49 | 59.77 | 77.75 Magnetic oxide (Fe_{3}O_{4}).| 37.82 | 77.01 | 28.12 | 3.88 Ferrous oxide (FeO). | 48.66 | | | +———+———+———+——— Total. | 86.48 | 85.41 | 87.89 | 81.63 +———+———+———+——— Percentage of total
oxygen reduced. | 24.03 | 10.02 | 2.26 | 0.49 Metallic iron. | 65.24 | 61.71 | 61.93 | 57.23 —————————–+———+———+———+———
NOTE.–All the carbon dioxide (CO_{2}) occurring in the ore as calcic carbonate was expelled.
_Third Experiment, Carbon monoxide_ (CO).–The tube A was filled with anthracite in the manner described for the second experiment, and heated to drive off the volatile matter, before the ore was placed in the upper tube, B, and the anthracite was divided from the ore by means of a piece of fine wire gauze. The lower tube, A, was heated to the temperature of white heat, the upper one, B, to a temperature of bright red. I. Layer, 1 in. thick from the bottom; ore dark brownish colored. II. Layer 4 in. thick above I.; ore reddish brown. III. Layer 11 in. thick above II.; ore red color. The analyses gave:
—————————–+———+———+——— | I. | II. | III.
+———+———+——— |per cent.|per cent.|per cent. Ferric oxide (Fe_{2}O_{3}). | 43.26 | 78.91 | 77.74 Ferrous oxide (FeO). | 37.86 | 3.46 | 1.44 +———+———+——— Total. | 81.12 | 82.37 | 79.18 +———+———+——— Calculated: | | |
Ferric oxide (Fe_{2}O_{3}). | … | 71.23 | 74.54 Magnetic oxide (Fe_{3}O_{4}).| 62.72 | 11.14 | 4.64 Ferrous oxide (FeO). | 18.40 | | +———+———+——— Total. | 81.12 | 82.37 | 79.18 +———+———+——— Percentage of total
oxygen reduced. | 16.44 | 1.49 | 0.42 Metallic iron. | 59.73 | 57.93 | 55.54 —————————–+———+———+———
NOTE.–The carbon monoxide (CO) had failed to remove from the ore the carbon dioxide existing as calcic carbonate. The summary of experiments in the following table appears to show that the water gas is a more powerful reducing agent than CO in proportion to the ratio of as
4.21 x 100
4.21 : 6.72, or ———— = 52 per cent. 72
Mr. B.D. Healey, Assoc. M. Inst. C.E., and the author are just now constructing large experimental plant in which water gas will be used as the reducing agent. This plant would have been at work before this but for some defects in the valvular arrangements, which will be entirely removed in the new modifications of the plant.
* * * * *
ANTISEPTIC MOUTH WASH.
Where an antiseptic mouth wash is needed, Mr. Sewill prescribes the use of perchloride of mercury in the following form: One grain of the perchloride and 1 grain of chloride of ammonium to be dissolved in 1 oz. of eau de Cologne or tincture of lemons, and a teaspoonful of the solution to be mixed with two-thirds of a wineglassful of water, making a proportion of about 1 of perchloride in 5,000 parts.–_Chemist and Druggist_.
* * * * *
ANNATTO.
[Footnote: Read at an evening meeting of the North British Branch of the Pharmaceutical Society, January 21.]
By WILLIAM LAWSON.
The subject which I have the honor to bring shortly before your notice this evening is one that formed the basis of some instructive remarks by Dr. Redwood in November, 1855, and also of a paper by Dr. Hassall, read before the Society in London in January, 1856, which latter gave rise to an animated discussion. The work detailed below was well in hand when Mr. MacEwan drew my attention to these and kindly supplied me with the volume containing reports of them. Unfortunately, they deal principally with the adulterations, while I was more particularly desirous to learn the composition in a general way, and especially the percentage of coloring resin, the important constituent in commercial annatto. Within the last few years it was one of the articles in considerable demand in this part of the country; now it is seldom inquired for. This, certainly, is not because butter coloring has ceased to be employed, and hence the reason for regretting that the percentage of resin was not dealt with in the articles referred to, so that a comparison could have been made between the commercial annatto of that period and that which exists now. In case some may not be in possession of literature bearing on it–which, by the way, is very meager–it may not be out of place to quote some short details as to its source, the processes for obtaining it, the composition of the raw material, and then the method followed in the present inquiry will be given, together with the results of the examination of ten samples; and though the subject doubtless has more interest for the country than for the town druggist, still, I trust it will have points of interest for both.
Annatto is the coloring matter derived from the seeds of an evergreen plant, _Bixa Orellana_, which grows in the East and West Indian Islands and South America, in the latter of which it is principally prepared. Two kinds are imported, Spanish annatto, made in Brazil, and flag or French, made mostly in Cayenne. These differ considerably in characters and properties, the latter having a disagreeable putrescent odor, while the Spanish is rather agreeable when fresh and good. It is, however, inferior to the flag as a coloring or dyeing agent. The seeds from which the substance is obtained are red on the outside, and two methods are followed in order to obtain it. One is to rub or wash off the coloring matter with water, allow it to subside, and to expose it to spontaneous evaporation till it acquires a pasty consistence. The other is to bruise the seeds, mix them with water, and allow fermentation to set in, during which the coloring matter collects at the bottom, from which it is subsequently removed and brought to the proper consistence by spontaneous evaporation. These particulars, culled from Dr. Redwood’s remarks, may suffice to show its source and the methods for obtaining it.
Dr. John gives the following as the composition of the pulp surrounding the seeds: Coloring resinous matter, 28; vegetable gluten, 26.5; ligneous fiber, 20; coloring, 20; extractive matter, 4; and a trace of spicy and acid matter.
It must be understood, however, that commercial annatto, having undergone processes necessary to fit it for its various uses, as well as to preserve it, differs considerably from this; and though it may not be true, as some hint, that manufacturing in this industry is simply a term synonymous with adulterating, yet results will afterward be given tending to show that there are articles in the market which have little real claim to the title. I tried, but failed, to procure a sample of raw material on which to work, with a view to learn something of its characters and properties in this state, and thus be able to contrast it with the manufactured or commercial article. The best thing to do in the circumstances, I thought, was to operate on the highest priced sample at disposal, and this was done in all the different ways that suggested themselves. The extraction of the resin by means of alcohol–the usual way, I believe–was a more troublesome operation than it appeared to be, as the following experiment will show: One hundred grains of No. 8 were taken, dried thoroughly, reduced to fine powder, and introduced into a flask containing 4 ounces of alcohol in the form of methylated spirit, boiled for an hour–the flask during the operation being attached to an inverted condenser–filtered off, and the residue treated with a smaller amount of the spirit and boiled for ten minutes. This was repeated with diminishing quantities until in all 14 ounces had been used before the alcoholic solution ceased to turn blue on the addition to it of strong sulphuric acid, or failed to give a brownish precipitate with stannous chloride. As the sample contained a considerable quantity of potassium carbonate, in which the resin is soluble, it was thought that by neutralizing this it might render the resin more easy of extraction. This was found to be so, but it was accompanied by such a mass of extractive as made it in the long run more troublesome, and hence it was abandoned. Thinking the spirit employed might be too weak, an experiment with commercial absolute alcohol was carried out as follows: One hundred grains of a red sample, No. 4, were thoroughly dried, powdered finely, and boiled in 2 ounces of the alcohol, filtered, and the residue treated with half an ounce more. This required to be repeated with fresh half ounces of the alcohol until in all 71/2 were used; the time occupied from first to last being almost three hours. This was considered unsatisfactory, besides being very expensive, and so it, also, was set aside, and a series of experiments with methylated spirit alone was set in hand. The results showed that the easiest and most satisfactory way was to take 100 grains (this amount being preferred, as it reduces error to the minimum), dry thoroughly, powder finely, and macerate with frequent agitation for twenty-four hours in a few ounces of spirit, then to boil in this spirit for a short time, filter, and repeat the boiling with a fresh ounce or so; this, as a rule, sufficing to completely exhaust it of its resin. Wynter Blyth says that the red resin, or bixin, is soluble in 25 parts of hot alcohol. It appears from these experiments that much more is required to dissolve it out of commercial annatto.
The full process followed consisted in determining the moisture by drying 100 grains at 212 deg. F. till constant, and taking this dried portion for estimation of the resin in the way just stated. The alcoholic extract was evaporated to dryness over a water-bath, the residue dissolved in solution of sodium carbonate, and the resin precipitated by dilute sulphuric acid (these reagents being chosen as the best after numerous trials with others), added in the slightest possible excess. The resin was collected on a tared double filter paper, washed with distilled water until the washings were entirely colorless, dried and weighed.
The ash was found in the usual way, and the extractive by the difference. In the ash the amount soluble was determined, and qualitatively examined, as was the insoluble portion in most of them.
The results are as follows:
| 1. | 2. | 3. | 4. | 5. | 6. | 7. | 8. | 9. | 10. Moisture | 21.75| 21.60| 20.39| 69.73| 18.00| 18.28| 15.71| 38.18| 19.33| 22.50 Resin | 3.00| 2.90| 1.00| 8.80| 3.00| 1.80| 5.40| 12.00| 5.90| 9.20 Extrac-
tive | 57.29| 59.33| 65.00| 19.47| 58.40| 65.67| 26.89| 20.82| 23.77| 28.50 Ash | 17.96| 16.17| 13.61| 2.00| 20.60| 14.25| 52.00| 29.00| 51.00| 39.80 ——————————————————————————- |100.00|100.00|100.00|100.00|100.00|100.00|100.00|100.00|100.00|100.00 ——————————————————————————- Ashes: | | | |Almost| | | | | | Soluble | 13.20| 12.57| 7.50|wholly| 10.0| 11.75| 18.5 | 20.0 | 15.0 | 13.8 Insoluble| 4.76| 3.60| 6.11| NaCl.| 10.6| 2.50| 33.5 | 9.0 | 36.0 | 26.0
The first six are the ordinary red rolls, with the exception of No. 4, which is a red mass, the only one of this class direct from the manufacturers. The remainder are brown cakes, all except No. 7 being from the manufacturers direct. The ash of the first two was largely common salt; that of No. 3 contained, besides this, iron in some quantity. No. 4 is unique in many respects. It was of a bright red color, and possessed a not disagreeable odor. It contained the largest percentage of moisture and the lowest of ash; had, comparatively, a large amount of coloring matter; was one of the cheapest, and in the course of some dairy trials, carried out by an intelligent farmer, was pronounced to be the best suited for coloring butter. So far as my experience goes, it was a sample of the best commercial excellence, though I fear the mass of water present and the absence of preserving substances will assist in its speedy decay. Were such an article easily procured in the usual way of business, there would not be much to complain of, but it must not be forgotten that it was got direct from the manufacturers–a somewhat suggestive fact when the composition of some other samples is taken into account. No. 5 emitted a disagreeable odor during ignition. The soluble portion of the ash was mostly common salt, and the insoluble contained three of sand–the highest amount found, although most of the reds contained some. No. 6 was a vile-looking thing, and when associated in one’s mind with butter gave rise to disagreeable reflections. It was wrapped in a paper saturated with a strongly smelling linseed oil. When it was boiled in water and broken up, hairs, among other things, were observed floating about. It contained some iron. The first cake, No. 7, gave off during ignition an agreeable odor resembling some of the finer tobaccos, and this is characteristic more or less of all the cakes. The ash weighed 52 per cent., the soluble part of which, 18.5, was mostly potassium carbonate, with some chlorides and sulphates; the insoluble, mostly chalk with iron and alumina. No. 8–highest priced of all–had in the mass an odor which I can compare to nothing else than a well rotted farmyard manure. Twenty parts of the ash were soluble and largely potassium carbonate, the insoluble being iron for the most part. The mineral portions of Nos. 9 and 10 closely resemble No. 7.
On looking over the results, it is found that the red rolls contained starchy matters in abundance (in No. 4 the starch was to a large extent replaced by water), and an ash, mostly sodium chloride, introduced no doubt to assist in its preservation as well as to increase the color of the resin–a well known action of salt on vegetable reds. The cakes, which are mostly used for cheese coloring, I believe, all appeared to contain turmeric, for they gave a more or less distinct reaction with the boric acid test, and all except No. 8 contained large quantities of chalk. These results in reference to extractive, etc., reveal nothing that has not been known before. Wynter Blyth, who gives the only analyses of annatto I have been able to find, states that the composition of a fair commercial sample (which I take to mean the raw article) examined by him was as follows: water, 24.2; resin, 28.8; ash, 22.5; and extractive, 24.5; and that of an adulterated (which I take to mean a manufactured) article, water, 13.4; resin, 11.0; ash (iron, silica, chalk, alumina, and common salt), 48.3; and extractive. 27.3. If this be correct, it appears that the articles at present in the market, or at least those which have come in my way, have been wretched imitations of the genuine thing, and should, instead of being called adulterated annatto, be called something else adulterated, but not seriously, with annatto. I have it on the authority of the farmer previously referred to, that 1/4 of an ounce of No. 4 is amply sufficient to impart the desired cowslip tint to no less than 60 lb. of butter. When so little is actually required, it does not seem of very serious importance whether the adulterant or preservative be flour, chalk, or water, but it is exasperating in a very high degree to have such compounds as Nos. 3 and 6 palmed off as decent things when even Nos. 1, 2, and 5 have been rejected by dairymen as useless for the purpose. In conclusion, I may be permitted to express the hope that others may be induced to examine the annatto taken into stock more closely than I was taught to do, and had been in the habit of doing, namely, to see if it had a good consistence and an odor resembling black sugar, for if so, the quality was above suspicion.
* * * * *
JAPANESE RICE WINE AND SOJA SAUCE.
Professor P. Cohn has recently described the mode in which he has manufactured the Japanese sake or rice wine in the laboratory. The material used was “Tane Kosi,” i.e., grains of rice coated with the mycelium, conidiophores, and greenish yellow chains of conidia of _Aspergillus Oryzoe_. The fermentation is caused by the mycelium of this fungus before the development of the fructification. The rice is first exposed to moist air so as to change the starch into paste, and then mixed with grains of the “Tane Kosi.” The whole mass of rice becomes in a short time permeated by the soft white shining mycelium, which imparts to it the odor of apple or pine-apple. To prevent the production of the fructification, freshly moistened rice is constantly added for two or three days, and then subjected to alcoholic fermentation from the _Saccharomyces_, which is always present in the rice, but which has nothing to do with the _Aspergillus_. The fermentation is completed in two or three weeks, and the golden yellow, sherry-like sake is poured off. The sample manufactured contained 13.9 per cent. of alcohol. Chemical investigation showed that the _Aspergillus_ mycelium transforms the starch into glucose, and thus plays the part of a diastase.
Another substance produced from the _Aspergillus_ rice is the soja sauce. The soja leaves, which contain little starch, but a great deal of oil and casein, are boiled, mixed with roasted barley, and then with the greenish yellow conidia powder of the _Aspergillus_. After the mycelium has fructified, the mass is treated with a solution of sodium chloride, which kills the _Aspergillus_, another fungus, of the nature of a _Chalaza_, and similar to that produced in the fermentation of “sauerkraut,” appearing in its place. The dark-brown soja sauce then separates.
* * * * *
ALUMINUM.
[Footnote: Annual address delivered by President J.A. Price before the meeting of the Scranton Board of Trade, Monday, January 18, 1886.]
By J.A. PRICE.
Iron is the basis of our civilization. Its supremacy and power it is impossible to overestimate; it enters every avenue of development, and it may be set down as the prime factor in the world’s progress. Its utility and its universality are hand in hand, whether in the magnificent iron steamship of the ocean, the network of iron rail upon land, the electric gossamer of the air, or in the most insignificant articles of building, of clothing, and of convenience. Without it, we should have miserably failed to reach our present exalted station, and the earth would scarcely maintain its present population; it is indeed the substance of substances. It is the Archimedean lever by which the great human world has been raised. Should it for a moment forget its cunning and lose its power, earthquake shocks or the wreck of matter could not be more disastrous. However axiomatic may be everything that can be said of this wonderful metal, it is undoubtedly certain that it must give way to a metal that has still greater proportions and vaster possibilities. Strange and startling as may seem the assertion, yet I believe it nevertheless to be true that we are approaching the period, if not already standing upon the threshold of the day, when this magical element will be radically supplanted, and when this valuable mineral will be as completely superseded as the stone of the aborigines. With all its apparent potency, it has its evident weaknesses; moisture is everywhere at war with it, gases and temperature destroy its fiber and its life, continued blows or motion crystallize and rob it of its strength, and acids will devour it in a night. If it be possible to eliminate all, or even one or more, of these qualities of weakness in any metal, still preserving both quantity and quality, that metal will be the metal of the future.
The coming metal, then, to which our reference is made is aluminum, the most abundant metal in the earth’s crust. Of all substances, oxygen is the most abundant, constituting about one-half; after oxygen comes silicon, constituting about one-fourth, with aluminum third in all the list of substances of the composition. Leaving out of consideration the constituents of the earth’s center, whether they be molten or gaseous, more or less dense as the case may be, as we approach it, and confining ourselves to the only practical phase of the subject, the crust, we find that aluminum is beyond question the most abundant and the most useful of all metallic substances.
It is the metallic base of mica, feldspar, slate, and clay. Professor Dana says: “Nearly all the rocks except limestones and many sandstones are literally ore-beds of the metal aluminum.” It appears in the gem, assuming a blue in the sapphire, green in the emerald, yellow in the topaz, red in the ruby, brown in the emery, and so on to the white, gray, blue, and black of the slates and clays. It has been dubbed “clay metal” and “silver made from clay;” also when mixed with any considerable quantity of carbon becoming a grayish or bluish black “alum slate.”
This metal in color is white and next in luster to silver. It has never been found in a pure state, but is known to exist in combination with nearly two hundred different minerals. Corundum and pure emery are ores that are very rich in aluminum, containing about fifty-four per cent. The specific gravity is but two and one-half times that of water; it is lighter than glass or as light as chalk, being only one-third the weight of iron and one-fourth the weight of silver; it is as malleable as gold, tenacious as iron, and harder than steel, being next the diamond. Thus it is capable of the widest variety of uses, being soft when ductility, fibrous when tenacity, and crystalline when hardness is required. Its variety of transformations is something wonderful. Meeting iron, or even iron at its best in the form of steel, in the same field, it easily vanquishes it at every point. It melts at 1,300 degrees F., or at least 600 degrees below the melting point of iron, and it neither oxidizes in the atmosphere nor tarnishes in contact with gases. The enumeration of the properties of aluminum is as enchanting as the scenes of a fairy tale.
Before proceeding further with this new wonder of science, which is already knocking at our doors, a brief sketch of its birth and development may be fittingly introduced. The celebrated French chemist Lavoisier, a very magician in the science, groping in the dark of the last century, evolved the chemical theory of combustion–the existence of a “highly respirable gas,” oxygen, and the presence of metallic bases in earths and alkalies. With the latter subject we have only to do at the present moment. The metallic base was predicted, yet not identified. The French Revolution swept this genius from the earth in 1794, and darkness closed in upon the scene, until the light of Sir Humphry Davy’s lamp in the early years of the present century again struck upon the metallic base of certain earths, but the reflection was so feeble that the great secret was never revealed. Then a little later the Swedish Berzelius and the Danish Oersted, confident in the prediction of Lavoisier and of Davy, went in search of the mysterious stranger with the aggressive electric current, but as yet to no purpose. It was reserved to the distinguished German Wohler, in 1827, to complete the work of the past fifty years of struggle and finally produce the minute white globule of the pure metal from a mixture of the chloride of aluminum and sodium, and at last the secret is revealed–the first step was taken. It took twenty years of labor to revolve the mere discovery into the production of the aluminum bead in 1846, and yet with this first step, this new wonder remained a foetus undeveloped in the womb of the laboratory for years to come.
Returning again to France some time during the years between 1854 and 1858, and under the patronage of the Emperor Napoleon III., we behold Deville at last forcing Nature to yield and give up this precious quality as a manufactured product. Rose, of Berlin, and Gerhard, in England, pressing hard upon the heels of the Frenchman, make permanent the new product in the market at thirty-two dollars per pound. The despair of three-quarters of a century of toilsome pursuit has been broken, and the future of the metal has been established.
The art of obtaining the metal since the period under consideration has progressed steadily by one process after another, constantly increasing in powers of productivity and reducing the cost. These arts are intensely interesting to the student, but must be denied more than a reference at this time. The price of the metal may be said to have come within the reach of the manufacturing arts already.
A present glance at the uses and possibilities of this wonderful metal, its application and its varying quality, may not be out of place. Its alloys are very numerous and always satisfactory; with iron, producing a comparative rust proof; with copper, the beautiful golden bronze, and so on, embracing the entire list of articles of usefulness as well as works of art, jewelry, and scientific instruments.
Its capacity to resist oxidation or rust fits it most eminently for all household and cooking utensils, while its color transforms the dark visaged, disagreeable array of pots, pans, and kitchen implements into things of comparative beauty. As a metal it surpasses copper, brass, and tin in being tasteless and odorless, besides being stronger than either.
It has, as we have seen, bulk without weight, and consequently may be available in construction of furniture and house fittings, as well in the multitudinous requirements of architecture. The building art will experience a rapid and radical change when this material enters as a component material, for there will be possibilities such as are now undreamed of in the erection of homes, public buildings, memorial structures, etc. etc., for in this metal we have the strength, durability, and the color to give all the variety that genius may dictate.
And when we take a still further survey of the vast field that is opening before us, we find in the strength without size a most desirable assistant in all the avenues of locomotion. It is the ideal metal for railway traffic, for carriages and wagons. The steamships of the ocean of equal size will double their cargo and increase the speed of the present greyhounds of the sea, making six days from shore to shore seem indeed an old time calculation and accomplishment. A thinner as well as a lighter plate; a smaller as well as a stronger engine; a larger as well as a less hazardous propeller; and a natural condition of resistance to the action of the elements; will make travel by water a forcible rival to the speed attained upon land, and bring all the distant countries in contact with our civilization, to the profit of all. This metal is destined to annihilate space even beyond the dream of philosopher or poet.
The tensile strength of this material is something equally wonderful, when wire drawn reaches as high as 128,000 pounds, and under other conditions reaches nearly if not quite 100,000 pounds to the square inch. The requirements of the British and German governments in the best wrought steel guns reach only a standard of 70,000 pounds to the square inch. Bridges may be constructed that shall be lighter than wooden ones and of greater strength than wrought steel and entirely free from corrosion. The time is not distant when the modern wonder of the Brooklyn span will seem a toy.
It may also be noted that this metal affords wide development in plumbing material, in piping, and will render possible the almost indefinite extension of the coming feature of communication and exchange–the pneumatic tube.
The resistance to corrosion evidently fits this metal for railway sleepers to take the place of the decaying wooden ties. In this metal the sleeper may be made as soft and yielding as lead, while the rail may be harder and tougher than steel, thus at once forming the necessary cushion and the avoidance of jar and noise, at the same time contributing to additional security in virtue of a stronger rail.
In conductivity this metal is only exceeded by copper, having many times that of iron. Thus in telegraphy there are renewed prospects in the supplanting of the galvanized iron wire–lightness, strength, and durability. When applied to the generation of steam, this material will enable us to carry higher pressure at a reduced cost and increased safety, as this will be accomplished by the thinner plate, the greater conductivity of heat, and the better fiber.
It is said that some of its alloys are without a rival as an anti-friction metal, and having hardness and toughness, fits it remarkably for bearings and journals. Herein a vast possibility in the mechanic art lies dormant–the size of the machine may be reduced, the speed and the power increased, realizing the conception of two things better done than one before. It is one of man’s creative acts.
From other of its alloys, knives, axes, swords, and all cutting implements may receive and hold an edge not surpassed by the best tempered steel. Hulot, director in the postage stamp department, Paris, asserts that 120,000 blows will exhaust the usefulness of the cushion of the stamp machine, and this number of blows is given in a day; and that when a cushion of aluminum bronze was substituted, it was unaffected after months of use.
If we have found a metal that possesses both tensile strength and resistance to compression; malleability and ductility–the quality of hardening, softening, and toughening by tempering; adaptability to casting, rolling, or forging; susceptibility to luster and finish; of complete homogeneous character and unusually resistant to destructive agents–mankind will certainly leave the present accomplishments as belonging to an effete past, and, as it were, start anew in a career of greater prospects.
This important material is to be found largely in nearly all the rocks, or as Prof. Dana has said, “Nearly all rocks are ore-beds of the metal.” It is in every clay bank. It is particularly abundant in the coal measures and is incidental to the shales or slates and clays that underlie the coal. This under clay of the coal stratum was in all probability the soil out of which grew the vegetation of the coal deposits. It is a compound of aluminum and other matter, and, when mixed with carbon and transformed by the processes of geologic action, it becomes the shale rock which we know and which we discard as worthless slate. And it is barely possible that we have been and are still carting to the refuse pile an article more valuable than the so greatly lauded coal waste or the merchantable coal itself. We have seen that the best alumina ore contains only fifty-four per cent. of metal.
The following prepared table has been furnished by the courtesy and kindness of Mr. Alex. H. Sherred, of Scranton.
ALUMINA.
Blue-black shale, Pine Brook drift 27.36 Slate from Briggs’ Shaft coal 15.93 Black fire clay, 4 ft. thick, Nos. 4 and 5 Rolling Mill mines 23.53 First cut on railroad, black clay above Rolling Mill 32.60 G vein black clay, Hyde Park mines 28.67
It will be seen that the black clay, shale, or slate, has a constituent of aluminum of from 15.93 per cent., the lowest, to 32.60 per cent., the highest. Under every stratum of coal, and frequently mixed with it, are these under deposits that are rich in the metal. When exposed to the atmosphere, these shales yield a small deposit of alum. In the manufacture of alum near Glasgow the shale and slate clay from the old coal pits constitute the material used, and in France alum is manufactured directly from the clay.
Sufficient has been advanced to warrant the additional assertion that we are here everywhere surrounded by this incomparable mineral, that it is brought to the surface from its deposits deep in the earth by the natural process in mining, and is only exceeded in quantity by the coal itself. Taking a columnar section of our coal field, and computing the thickness of each shale stratum, we have from twenty-five to sixty feet in thickness of this metal-bearing substance, which averages over twenty-five per cent. of the whole in quantity in metal.
It is readily apparent that the only task now before us is the reduction of the ore and the extraction of the metal. Can this be done? We answer, it has been done. The egg has stood on end–the new world has been sighted. All that now remains is to repeat the operation and extend the process. Cheap aluminum will revolutionize industry, travel, comfort, and indulgence, transforming the present into an even greater civilization. Let us see.
We have seen the discovery of the mere chemical existence of the metal, we have stood by the birth of the first white globule or bead by Wohler, in 1846, and witnesssed its introduction as a manufactured product in 1855, since which time, by the alteration and cheapening of one process after another, it has fallen in price from thirty-two dollars per pound in 1855 to fifteen dollars per pound in 1885. Thirty years of persistent labor at smelting have increased the quantity over a thousandfold and reduced the cost upward of fifty per cent.
All these processes involve the application of heat–a mere question of the appliances. The electric currents of Berzelius and Oersted, the crucible of Wohler, the closed furnaces and the hydrogen gas of the French manufacturers and the Bessemer converter apparatus of Thompson, all indicate one direction. This metal can be made to abandon its bed in the earth and the rock at the will of man. During the past year, the Messrs. Cowles, of Cleveland, by their electric smelting process, claim to have made it possible to reduce the price of the metal to below four dollars per pound; and there is now erecting at Lockport, New York, a plant involving one million of capital for the purpose.
Turning from the employment of the expensive reducing agents to the simple and sole application of heat, we are unwilling to believe that we do not here possess in eminence both the mineral and the medium of its reduction. Whether the electric or the reverberatory or the converter furnace system be employed, it is surely possible to produce the result.
To enter into consideration of the details of these constructions would involve more time than is permitted us on this occasion. They are very interesting. We come again naturally to the limitless consideration of powdered fuel, concerning which certain conclusions have been reached. In the dissociation of water into its hydrogen and oxygen, with the mingled carbon in a powdered state, we undoubtedly possess the elements of combustion that are unexcelled on earth, a heat-producing combination that in both activity and power leaves little to be desired this side of the production of the electric force and heat directly from the carbon without the intermediary of boilers, engines, dynamos, and furnaces.
In the hope of stimulating thought to this infinite question of proper fuel combustion, with its attendant possibilities for man’s gratification and ambition, this advanced step is presented. The discussion of processes will require an amount of time which I hope this Board will not grudgingly devote to the subject, but which is impossible at present. Do not forget that there is no single spot on the face of the globe where nature has lavished more freely her choicest gifts. Let us be active in the pursuit of the treasure and grateful for the distinguished consideration.
* * * * *
THE ORIGIN OF METEORITES.
On January 9, Professor Dewar delivered the sixth and last of his series of lectures at the Royal Institution on “The Story of a Meteorite.” [For the preceding lectures, see SUPPLEMENTS 529 and 580.] He said that cosmic dust is found on Arctic snows and upon the bottom of the ocean; all over the world, in fact, at some time or other, there has been a large deposit of this meteoric dust, containing little round nodules found also in meteorites. In Greenland some time ago numbers of what were supposed to be meteoric stones were found; they contained iron, and this iron, on being analyzed at Copenhagen, was found to be rich in nickel. The Esquimaux once made knives from iron containing nickel; and as any such alloy they must have found and not manufactured, it was supposed to be of meteoric origin. Some young physicists visited the basaltic coast in Greenland from which some of the supposed meteoric stones had been brought, and in the middle of the rock large nodules were found composed of iron and nickel; it, therefore, became evident that the earth might produce masses not unlike such as come to us as meteorites. The lecturer here exhibited a section of the Greenland rock containing the iron, and nickel alloy, mixed with stony crystals, and its resemblance to a section of a meteorite was obvious. It was 21/2 times denser than water, yet the whole earth is 51/2 times denser than water, so that if we could go deep enough, it is not improbable that our own globe might be found to contain something like meteoric iron. He then called attention to the following tables:
_Elementary Substances found in Meteorites_.
Hydrogen. Chromium. Arsenic.
Lithium. Manganese. Vanadium? Sodium. Iron. Phosphorus.
Potassium. Nickel. Sulphur.
Magnesium. Cobalt. Oxygen.
Calcium. Copper. Silicon.
Aluminum. Tin. Carbon.
Titanium. Antimony. Chlorine.
_Density of Meteorites_.
Carbonaceous (Orgueil, etc.) 1.9 to 3 Aluminous (Java) 3.0 ” 3.2
Peridotes (Chassigny, etc.) 3.5 ” — Ordinary type (Saint Mes) 3.1 ” 3.8
Rich in iron (Sierra de Chuco) 6.5 ” 7.0 Iron with stone (Krasnoyarsk) 7.1 ” 7.8 True irons (Caille) 7.0 ” 8.0
_Interior of the Earth_
Parts
of the
radius. Density.
0.0 11.0
0.1 10.3
0.2 9.6
0.3 8.9
0.4 8.3
0.5 7.8
0.6 7.4
0.7 7.1
0.8 6.2
0.9 5.0
1.0 2.6
[Illustration]
Twice a year, said Professor Dewar, what are called “falling stars” maybe plentifully seen; the times of their appearance are in August and November. Although thousands upon thousands of such small meteors have passed through our atmosphere, there is no distinct record of one having ever fallen to the earth during these annual displays. One was said to have fallen recently at Naples, but on investigation it turned out to be a myth. These annual meteors in the upper air are supposed to be only small ones, and to be dissipated into dust and vapor at the time of their sudden heating; so numerous are they that 40,000 have been counted in one evening, and an exceptionally great display comes about once in 331/4 years. The inference from their periodicity is, that they are small bodies moving round the sun in orbits of their own, and that whenever the earth crosses their orbits, thereby getting into their path, a splendid display of meteors results. A second display, a year later, usually follows the exceptionally great display just mentioned, consequently the train of meteors is of great length. Some of these meteors just enter the atmosphere of the earth, then pass out again forever, with their direction of motion altered by the influence of the attraction of the earth. He here called attention to the accompanying diagram of the orbits of meteors.
The lecturer next invited attention to a hollow globe of linen or some light material; it was about 2 ft. or 2 ft. 6 in. in diameter, and contained hidden within it the great electro-magnet, weighing 2 cwt., so often used by Faraday in his experiments. He also exhibited a ball made partly of thin iron; the globe represented the earth, for the purposes of the experiment, and the ball a meteorite of somewhat large relative size. The ball was then discharged at the globe from a little catapult; sometimes the globe attracted the ball to its surface, and held it there, sometimes it missed it, but altered its curve of motion through the air. So was it, said the lecturer, with meteorites when they neared the earth. Photographs from drawings, by Professor A. Herschel, of the paths of meteors as seen by night were projected on the screen; they all seemed to emanate from one radiant point, which, said the lecturer, is a proof that their motions are parallel to each other; the parallel lines seem to draw to a point at the greatest distance, for the same reason that the rails of a straight line of railway seem to come from a distant central point. The most interesting thing about the path of a company of meteors is, that a comet is known to move in the same orbit; the comet heads the procession, the meteors follow, and they are therefore, in all probability, parts of comets, although everything about these difficult matters cannot as yet be entirely explained; enough, however, is known to give foundation for the assumption that meteorites and comets are not very dissimilar.
The light of a meteorite is not seen until it enters the atmosphere of the earth, but falling meteorites can be vaporized by electricity, and the light emitted by their constituents be then examined with the spectroscope. The light of comets can be directly examined, and it reveals the presence in those bodies of sodium, carbon, and a few other well-known substances. He would put a piece of meteorite in the electric arc to see what light it would give; he had never tried the experiment before. The lights of the theater were then turned down, and the discourse was continued in darkness; among the most prominent lines visible in the spectrum of the meteorite, Professor Dewar specified magnesium, sodium, and lithium. “Where do meteorites come from?” said the lecturer. It might be, he continued, that they were portions of exploded planets, or had been ejected from planets. In this relation, he should like to explain the modern idea of the possible method of construction of our own earth. He then set forth the nebular hypothesis that at some long past time our sun and all his planets existed but as a volume of gas, which in contracting and cooling formed a hot volume of rotating liquid, and that as this further contracted and cooled, the planets, and moons, and planetary rings fell off from it and gradually solidified, the sun being left as the solitary comparatively uncooled portion of the original nebula. In partial illustration of this, he caused a little globe of oil, suspended in an aqueous liquid of nearly its own specific gravity, to rotate, and as it rotated it was seen, by means of its magnified image upon the screen, to throw off from its outer circumference rings and little globes.
* * * * *
CANDELABRA CACTUS AND CALIFORNIA WOODPECKER.
By C.F. HOLDER.
One of the most picturesque objects that meet the eye of the traveler over the great plains of the southern portion of California and New Mexico is the candelabra cactus. Systematically it belongs to the Cereus family, in which the notable Night-blooming Cereus also is naturally included. In tropical or semi-tropical countries these plants thrive, and grow to enormous size. For example, the Cereus that bears those great flowers, and blooms at night, exhaling powerful perfume, as we see them in hothouses in our cold climate, are even in the semi-tropical region of Key West, on the Florida Reef, seen to grow enormously in length.
[Illustration: THE CANDELABRA CACTUS–CEREUS GIGANTEUS.]
We cultivated several species of the more interesting forms during a residence on the reef. Our brick house, two stories in height, was entirely covered on a broad gable end, the branches more than gaining the top. There is a regular monthly growth, and this is indicated by a joint between each two lengths. Should the stalk be allowed to grow without support, it will continue growing without division, and exhibit stalks five or six feet in length, when they droop, and fall upon the ground.
Where there is a convenient resting place on which it can spread out and attach itself, the stalk throws out feelers and rootlets, which fasten securely to the wall or brickwork; then, this being a normal growth, there is a separation at intervals of about a foot. That is, the stalk grows in one month about twelve inches, and if it has support, the middle woody stalk continues to grow about an inch further, but has no green, succulent portion, in fact, looks like a stem; then the other monthly growth takes place, and ends with a stem, and so on indefinitely. Our house was entirely covered by the stems of such a plant, and the flowers were gorgeous in the extreme. The perfume, however, was so potent that it became a nuisance. Such is the Night-blooming Cereus in the warm climates, and similarly the Candelabra Cereus grows in stalks, but architecturally erect, fluted like columns. The flowers are large, and resemble those of the night-blooming variety. Some columns remain single, and are amazingly artificial appearing; others throw off shoots, as seen in the picture. There are some smaller varieties that have even more of a candelabra look, there being clusters of side shoots, the latter putting out from the trunk regularly, and standing up parallel to each other. The enormous size these attain is well shown in the picture.
Whenever the great stalks of these cacti die, the succulent portion is dried, and nothing is left but the woody fiber. They are hollow in places, and easily penetrated. A species of woodpecker, _Melanerpes formicivorus_, is found to have adopted the use of these dry stalks for storing the winter’s stock of provisions. There are several round apertures seen on the stems in the pictures, which were pecked by this bird. This species of woodpecker is about the size of our common robin or migratory thrush, and has a bill stout and sharp. The holes are pecked for the purpose of storing away acorns or other nuts; they are just large enough to admit the fruit, while the cup or larger end remains outside. The nuts are forced in, so that it requires considerable wrenching to dislodge them. In many instances the nuts are so numerous, the stalk has the appearance of being studded with bullets. This appearance is more pronounced in cases where the dead trunk of an oak is used. There are some specimens of the latter now owned by the American Museum of Natural History, which were originally sent to the Centennial Exhibition at Philadelphia. They were placed in the department contributed by the Pacific Railroad Company, and at that time were regarded as some of the wonders of that newly explored region through which the railroad was then penetrating. Some portions of the surface of these logs are nearly entirely occupied by the holes with acorns in them. The acorns are driven in very tightly in these examples; much more so than in the cactus plants, as the oak is nearly round, and the holes were pecked in solid though dead wood. One of the most remarkable circumstances connected with this habit of the woodpecker is the length of flight required and accomplished. At Mount Pizarro, where such storehouses are found, the nearest oak trees are in the Cordilleras, thirty miles distant; thus the birds are obliged to make a journey of sixty miles to accomplish the storing of one acorn. At first it seemed strange that a bird should spend so much labor to place those bits of food, and so far away. De Saussure, a Swiss naturalist, published in the _Bibliotheque Universelle_, of Geneva, entertaining accounts of the Mexican Colaptes, a variety of the familiar “high hold,” or golden winged woodpecker. They were seen to store acorns in the dead stalks of the maguey (_Agave Americana_). Sumichrast, who accompanied him to Central America, records the same facts. These travelers saw great numbers of the woodpeckers in a region on the slope of a range of volcanic mountains. There was little else of vegetation than the _Agave_, whose barren, dead stems were studded with acorns placed there by the woodpeckers.
The maguey throws up a stalk about fifteen feet in height yearly, which, after flowering, grows stalky and brittle, and remains an unsightly thing. The interior is pithy, but after the death of the stalk the pith contracts, and leaves the greater portion of the interior hollow, as we have seen in the case of the cactus branches. How the birds found that these stalks were hollow is a problem not yet solved, but, nevertheless, they take the trouble to peck away at the hard bark, and once penetrated, they commence to fill the interior; when one space is full, the bird pecks a little higher up, and so continues.
Dr. Heerman, of California, describes the California _Melanerpes_ as one of the most abundant of the woodpeckers; and remarks that it catches insects on the wing like a flycatcher. It is well determined that it also eats the acorns that it takes so much pains to transport.
[Illustration: FLOWER OF CEREUS GIGANTEUS.]
It seems that these birds also store the pine trees, as well as the oaks. It is not quite apparent why these birds exhibit such variation in habits; they at times select the more solid trees, where the storing cannot go on without each nut is separately set in a hole of its own. There seems an instinct prompting them to do this work, though there may not be any of the nuts touched again by the birds. Curiously enough, there are many instances of the birds placing pebbles instead of nuts in holes they have purposely pecked for them. Serious trouble has been experienced by these pebbles suddenly coming in contact with the saw of the mill through which the tree is running. The stone having been placed in a living tree, as is often the case, its exterior had been lost to sight during growth.
Some doubt has been entertained about the purpose of the bird in storing the nuts in this manner. De Saussure tells us he has witnessed the birds eating the acorns after they had been placed in holes in trees, and expresses his conviction that the insignificant grub which is only seen in a small proportion of nuts is not the food they are in search of.
C.W. Plass, Esq., of Napa City, California, had an interesting example of the habits of the California _Melanerpes_ displayed in his own house. The birds had deposited numbers of acorns in the gable end. A considerable number of shells were found dropped underneath the eaves, while some were found in place under the gable, and these were perfect, having no grubs in them.
The picture shows a very common scene in New Mexico. The columns, straight and angular, are often sixty feet in height. It is called torch cactus in some places. There are many varieties, and as many different shapes. Some lie on the ground; others, attached to trunks of trees as parasites, hang from branches like great serpents; but none is so majestic as the species called systematically _Cereus giganteus_, most appropriately. The species growing pretty abundantly on the island of Key West is called candle cactus. It reaches some ten or twelve feet, and is about three inches in diameter. The angles are not so prominent, which gives the cylinders a roundish appearance. They form a pretty, rather picturesque feature in the otherwise barren undergrowth of shrubbery and small trees. Accompanied by a few flowering cocoa palms, the view is not unpleasing. The fiber of these plants is utilized in some coarse manufactures. The maguey, or Agave, is used in the manufacture of fine roping. Manila hemp is made from a species. The species whose dried stalks are used by the woodpeckers for their winter storage was cultivated at Key West, Florida, during several years before 1858. Extensive fields of the Agave stood unappropriated at that period. Considerable funds were dissipated on this venture. Extensive works were established, and much confidence was entertained that the scheme would prove a paying one, but the “hemp” rope which this was intended to rival could be made cheaper than this. The great Agave plants, with their long stalks, stand now, increasing every year, until a portion of the island is overrun with them.
CEREUS GIGANTEUS.
This wonderful cactus, its colossal proportions, and weird, yet grand, appearance in the rocky regions of Mexico and California, where it is found in abundance, have been made known to us only through books of travel, no large plants of it having as yet appeared in cultivation in this country. It is questionable if ever the natural desire to see such a vegetable curiosity represented by a large specimen in gardens like Kew can be realized, owing to the difficulty of importing large stems in a living condition; and even if successfully brought here, they survive only a very short time. To grow young plants to a large size seems equally beyond our power, as plants 6 inches high and carefully managed are quite ten years old. When young, the stem is globose, afterward becoming club-shaped or cylindrical. It flowers at the height of 12 feet, but grows up to four or five times that height, when it develops lateral branches, which curve upward and present the appearance of an immense candelabrum, the base of the stem being as thick as a man’s body. The flower, of which a figure is given here, is about 5 inches long and wide, the petals cream colored, the sepals greenish white. Large clusters of flowers are developed together near the top of the stem. A richly colored edible fruit like a large fig succeeds each flower, and this is gathered by the natives and used as food under the name of saguarro. A specimen of this cactus 3 feet high may be seen in the succulent house at Kew.–_B., The Garden_.
* * * * *
HOW PLANTS ARE REPRODUCED.
[Footnote: Read at a meeting of the Chemists’ Assistants’ Association. December 16, 1885.]
By C.E. STUART, B.Sc.
In two previous papers read before this Association I have tried to condense into as small a space as I could the processes of the nutrition and of the growth of plants; in the present paper I want to set before you the broad lines of the methods by which plants are reproduced.
Although in the great trees of the conifers and the dicotyledons we have apparently provision for growth for any number of years, or even centuries, yet accident or decay, or one of the many ills that plants are heirs to, will sooner or later put an end to the life of every individual plant.
Hence the most important act of a plant–not for itself perhaps, but for its race–is the act by which it, as we say, “reproduces itself,” that is, the act which results in the giving of life to a second individual of the same form, structure, and nature as the original plant.
The methods by which it is secured that the second generation of the plant shall be as well or even better fitted for the struggle of life than the parent generation are so numerous and complicated that I cannot in this paper do more than allude to them; they are most completely seen in cross fertilization, and the adaptation of plant structures to that end.
What I want to point out at present are the principles and not so much the details of reproduction, and I wish you to notice, as I proceed, what is true not only of reproduction in plants but also of all processes in nature, namely, the paucity of typical methods of attaining the given end, and the multiplicity of special variation from those typical methods. When we see the wonderfully varied forms of plant life, and yet learn that, so to speak, each edifice is built with the same kind of brick, called a cell, modified in form and function; when we see the smallest and simplest equally with the largest and most complicated plant increasing in size subject to the laws of growth by intussusception and cell division, which are universal in the organic world; we should not be surprised if all the methods by which plants are reproduced can be reduced to a very small number of types.
The first great generalization is into–
1. The vegetative type of reproduction, in which one or more ordinary cells separate from the parent plant and become an independent plant; and–
2. The special-cell type of reproduction, in which either one special cell reproduces the plant, or two special cells by their union form the origin of the new plant; these two modifications of the process are known respectively as asexual and sexual.
The third modification is a combination of the two others, namely, the asexual special cell does not directly reproduce its parent form, but gives rise to a structure in which sexual special cells are developed, from whose coalescence springs again the likeness of the original plant. This is termed alternation of generations.
The sexual special cell is termed the _spore_.
The sexual special cells are of one kind or of two kinds.
Those which are of one kind may be termed, from their habit of yoking themselves together, _zygoblasts_, or conjugating cells.
Those which are of two kinds are, first, a generally aggressive and motile fertilizing or so-called “male cell,” called in its typical form an _antherozoid_; and, second, a passive and motionless receptive or so-called “female cell,” called an _oosphere_.
The product of the union of two zygoblasts is termed a _zygospore_.
The product of the union of an antherozoid and an oosphere is termed an _oospore_.
In many cases the differentiation of the sexual cells does not proceed so far as the formation of antherozoids or of distinct oospheres; these cases I shall investigate with the others in detail presently.
First, then, I will point out some of the modes of vegetative reproduction.
The commonest of these is cell division, as seen in unicellular plants, such as protococcus, where the one cell which composes the plant simply divides into two, and each newly formed cell is then a complete plant.
The particular kind of cell division termed “budding” here deserves mention. It is well seen in the yeast-plant, where the cell bulges at one side, and this bulge becomes larger until it is nipped off from the parent by contraction at the point of junction, and is then an independent plant.
Next, there is the process by which one plant becomes two by the dying off of some connecting portion between two growing parts.
Take, for instance, the case of the liverworts. In these there is a thallus which starts from a central point and continually divides in a forked or dichotomous manner. Now, if the central portion dies away, it is obvious that there will be as many plants as there were forkings, and the further the dying of the old end proceeds, the more young plants will there be.
Take again, among higher plants, the cases of suckers, runners, stolons, offsets, etc. Here, by a process of growth but little removed from the normal, portions of stems develop adventitious roots, and by the dying away of the connecting links may become independent plants.
Still another vegetative method of reproduction is that by bulbils or gemmae.
A bulbil is a bud which becomes an independent plant before it commences to elongate; it is generally fleshy, somewhat after the manner of a bulb, hence its name. Examples occur in the axillary buds of _Lilium bulbiferum_, in some _Alliums_, etc.
The gemma is found most frequently in the liverworts and mosses, and is highly characteristic of these plants, in which indeed vegetative reproduction maybe said to reach its fullest and most varied extent.
Gemmae are here formed in a sort of flat cup, by division of superficial cells of the thallus or of the stem, and they consist when mature of flattened masses of cells, which lie loose in the cup, so that wind or wet will carry them away on to soil or rock, when, either by direct growth from apical cells, as with those of the liverworts, or with previous emission of thread-like cells forming a “protonema,” in the case of the mosses, the young plant is produced from them.
The lichens have a very peculiar method of gemmation. The lichen-thallus is composed of chains or groups of round chlorophyl-containing cells, called “gonidia,” and masses of interwoven rows of elongated cells which constitute the hyphae. Under certain conditions single cells of the gonidia become surrounded with a dense felt of hyphae, these accumulate in numbers below the surface of the thallus, until at last they break out, are blown or washed away, and start germination by ordinary cell division, and thus at once reproduce a fresh lichen-thallus. These masses of cells are called soredia.
Artificial budding and grafting do not enter into the scope of this paper.
As in the general growth and the vegetative reproduction of plants cell-division is the chief method of cell formation, so in the reproduction of plants by special cells the great feature is the part played by cells which are produced not by the ordinary method of cell division, but by one or the other processes of cell formation, namely, free-cell formation or rejuvenescence.
If we broaden somewhat the definition of rejuvenescence and free-cell formation, and do not call the mother-cells of spores of mosses, higher cryptogams, and also the mother-cells of pollen-grains, reproductive cells, which strictly speaking they are not, but only producers of the spores or pollen-grains, then we may say that _cell-division is confined to vegetative processes, rejuvenescence and free-cell formation are confined to reproductive processes_.
Rejuvenescence may be defined as the rearrangement of the whole of the protoplasm of a cell into a new cell, which becomes free from the mother-cell, and may or may not secrete a cell-wall around it.
If instead of the whole protoplasm of the cell arranging itself into one mass, it divides into several, or if portions only of the protoplasm become marked out into new cells, in each case accompanied by rounding off and contraction, the new cells remaining free from one another, and usually each secreting a cell wall, then this process, whose relation to rejuvenescence is apparent, is called free-cell formation.
The only case of purely vegetative cell-formation which takes place by either of these processes is that of the formation of endosperm in Selaginella and phanerogams, which is a process of free-cell formation.
On the other hand, the universal contraction and rounding off of the protoplasm, and the formation by either rejuvenescence or free-cell formation, distinctly mark out the special or true reproductive cell.
Examples of reproductive cells formed by rejuvenescence are:
1. The swarm spores of many algae, as Stigeoclonium (figured in Sachs’ “Botany”). Here the contents of the cell contract, rearrange themselves, and burst the side of the containing wall, becoming free as a reproductive cell.
2. The zygoblasts of conjugating algae, as in Spirogyra. Here the contents of a cell contract and rearrange themselves only after contact of the cell with one of another filament of the plant. This zygoblast only becomes free after the process of conjugation, as described below.
3. The oosphere of characeae, mosses and liverworts, and vascular cryptogams, where in special structures produced by cell-divisions there arise single primordial cells, which divide into two portions, of which the upper portion dissolves or becomes mucilaginous, while the lower contracts and rearranges itself to form the oosphere.
4. Spores of mosses and liverworts, of vascular cryptogams, and pollen cells of phanerogams, which are the analogue of the spores.
The type in all these cases is this: A mother-cell produces by cell-division four daughter-cells. This is so far vegetative. Each daughter-cell contracts and becomes more or less rounded, secretes a wall of its own, and by the bursting or absorption of the wall of its mother-cell becomes free. This is evidently a rejuvenescence.
Examples of reproductive cells formed by free-cell formation are:
1. The ascospores of fungi and algae.
2. The zoospores or mobile spores of many algae and fungi.
3. The germinal vesicles of phanerogams.
The next portion of my subject is the study of the methods by which these special cells reproduce the plant.
1st. Asexual methods.
1. Rejuvenescence gives rise to a swarm-spore or zoospore. The whole of the protoplasm of a cell contracts, becomes rounded and rearranged, and escapes into the water, in which the plant floats as a mass of protoplasm, clear at one end and provided with cilia by which it is enabled to move, until after a time it comes to rest, and after secreting a wall forms a new plant by ordinary cell-division. Example: Oedogonium.
2. Free-cell formation forms swarm-spores which behave as above. Example: Achlya.
3. Free-cell formation forms the typical motionless spore of algae and fungi. For instance, in the asci of lichens there are formed from a portion of the protoplasm four or more small ascospores, which secrete a cell-wall and lie loose in the ascus. Occasionally these spores may consist of two or more cells. They are set free by the rupture of the ascus, and germinate by putting out through their walls one or more filaments which branch and form the thallus of a new individual. Various other spores formed in the same way are known as _tetraspores_, etc.
4. Cell-division with rejuvenescence forms the spores of mosses and higher cryptogams.
To take the example of moss spores:
Certain cells in the sporogonium of a moss are called mother-cells. The protoplasm of each one of these becomes divided into four parts. Each of these parts then secretes a cell-wall and becomes free as a spore by the rupture or absorption of the wall of the mother-cell. The germination of the spores I shall describe later.
5. A process of budding which in the yeast plant and in mosses is merely vegetatively reproductive, in fungi becomes truly reproductive, namely, the buds are special cells arising from other special cells of the hyphae.
For example, the so-called “gills” of the common mushroom have their surface composed of the ends of the threads of cells constituting the hyphae. Some of these terminal cells push out a little finger of protoplasm, which swells, thickens its wall, and becomes detached from the mother-cell as a spore, here called specially a _basidiospore_.
Also in the common gray mould of infusions and preserves, Penicillium, by a process which is perhaps intermediate between budding and cell-division, a cell at the end of a hypha constricts itself in several places, and the constricted portions become separate as _conidiospores_.
_Teleutospores, uredospores_, etc., are other names for spores similarly formed.
These conidiospores sometimes at once develop hyphae, and sometimes, as in the case of the potato fungus, they turn out their contents as a swarm-spore, which actively moves about and penetrates the potato leaves through the stomata before they come to rest and elongate into the hyphal form.
So far for asexual methods of reproduction.
I shall now consider the sexual methods.
The distinctive character of these methods is that the cell from which the new individual is derived is incapable of producing by division or otherwise that new individual without the aid of the protoplasm of another cell.
Why this should be we do not know; all that we can do is to guess that there is some physical or chemical want which is only supplied through the union of the two protoplasmic masses. The process is of benefit to the species to which the individuals belong, since it gives it a greater vigor and adaptability to varying conditions, for the separate peculiarities of two individuals due to climatic or other conditions are in the new generation combined in one individual.
The simplest of the sexual processes is conjugation. Here the two combining cells are apparently of precisely similar nature and structure. I say apparently, because if they are really alike it is difficult to see what is gained by the union.
Conjugation occurs in algae and fungi. A typical case is that of Spirogyra. This is an alga with its cells in long filaments. Two contiguous cells of two parallel filaments push each a little projection from its cell-wall toward the other. When these meet, the protoplasm of each of the two cells contracts, and assumes an elliptical form–it undergoes rejuvenescence. Next an opening forms where the two cells are in contact, and the contents of one cell pass over into the other, where the two protoplasmic bodies coalesce, contract, and develop a cell-wall. The zygospore thus formed germinates after a long period and forms a new filament of cells.
Another example of conjugation is that of Pandorina, an alga allied to the well-known volvox. Here the conjugating cells swim free in water; they have no cell-wall, and move actively by cilia. Two out of a number approach, coalesce, contract, and secrete a cell-wall. After a long period of rest, this zygospore allows the whole of its contents to escape as a swarm-spore, which after a time secretes a gelatinous wall, and by division reproduces the sixteen-celled family.
We now come to fertilization, where the uniting cells are of two kinds.
The simplest case is that of Vaucheria, an alga. Here the vegetative filament puts out two protuberances, which become shut off from the body of the filament by partitions. The protoplasm in one of these protuberances arranges itself into a round mass–the oosphere or female cell. The protoplasm of the other protuberance divides into many small masses, furnished with cilia, the spermatozoids or male cells. Each protuberance bursts, and some of the spermatozoids come in contact with and are absorbed by the oosphere, which then secretes a cell-wall, and after a time germinates.
The most advanced type of fertilization is that of angiosperms.
In them there are these differences from the above process: the contents of the male cell, represented by the pollen, are not differentiated into spermatozoids, and there is no actual contact between the contents of the pollen tube and the germinal vesicle, but according to Strashurger, there is a transference of the substance of the nucleus of the pollen cell to that of the germinal vesicle by osmose. The coalescence of the two nuclei within the substance of the germinal vesicle causes the latter to secrete a wall, and to form a new plant by division, being nourished the while by the mother plant, from whose tissues the young embryo plant contained in the seed only becomes free when it is in an advanced stage of differentiation.
Perhaps the most remarkable cases of fertilization occur in the Florideae or red seaweeds, to which class the well-known Irish moss belongs.
Here, instead of the cell which is fertilized by the rounded spermatozoid producing a new plant through the medium of spores, some other cell which is quite distinct from the primarily fertilized cell carries on the reproductive process.
If the allied group of the Coleochaeteae is considered together with the Florideae, we find a transition between the ordinary case of Coleochaete and that of Dudresnaya. In Coleochaete, the male cell is a round spermatozoid, and the female cell an oosphere contained in the base of a cell which is elongated into an open and hair-like tube called the trichogyne. The spermatozoid coalesces with the oosphere, which secretes a wall, becomes surrounded with a covering of cells called a cystocarp, which springs from cells below the trichogyne, and after the whole structure falls from the parent plant, spores are developed from the oospore, and from them arises a new generation.
In Dudresnaya, on the other hand, the spermatozoid coalesces indeed with the trichogyne, but this does not develop further. From below the trichogyne, however, spring several branches, which run to the ends of adjacent branches, with the apical cells of which they conjugate, and the result of this conjugation is the development of a cystocarp similar to that of Coleochaete. The remarkable point here is the way in which the effect of the fertilizing process is carried from one cell to another entirely distinct from it.
Thus I have endeavored to sum up the processes of asexual and of sexual reproduction. But it is a peculiar characteristic of most classes of plants that the cycle of their existence is not complete until both methods of reproduction have been called into play, and that the structure produced by one method is entirely different from that produced by the other method.
Indeed, it is only in some algae and fungi that the reproductive cells of one generation produce a generation similar to the parent; in all other plants a generation A produces are unlike generation B, which may either go on to produce another generation, C, and then back to A, or it may go on producing B’s until one of these reproduces A, or again it may directly reproduce; A. Thus we have the three types:
1. A-B-C.–A-B-C.–A………………… etc. 2. A-B-B.–B-B……………….B–A … etc. 3. A B A B A……………………….. etc.
The first case is not common, the usual number of generations being two only; but a typical example of the occurrence of three generations is in such fungi as _Puccinia Graminis_. Here the first generation grows on barberry leaves, and produces a kind of spore called an _aecidium spore_. These aecidium spores germinate only on a grass stem or leaf, and a distinct generation is produced, having a particular kind of spore called an _uredospore_. The uredospore forms fresh generations of the same kind until the close of the summer, when the third generation with another kind of spore, called a _teleutospore_, is produced.
The teleutospores only germinate on barberry leaves, and there reproduce the original aecidium generation.
Thus we have the series A.B.B.B … BCA
In this instance all the generations are asexual, but the most common case is for the sexual and the asexual generations to alternate. I will describe as examples the reproduction of a moss, a fern, and a dicotyledon.
In such a typical moss as Funaria, we have the following cycle of developments: The sexual generation is a dioecious leafy structure, having a central elongated axis, with leaves arranged regularly around