proper strength, will make a perfect liniment.
_Linimentum Calcis_.–Cotton seed oil is not at all adapted to making this liniment. It does not readily saponify, separates quickly, and it is almost impossible to unite when separated.
_Linimentum Camphorae_.–Cotton seed oil is far superior to olive oil in making this liniment, it being a much better solvent of camphor. It has not that disagreeable odor so commonly found in the liniment.
_Linimentum Chloroformi_.–Cotton seed oil being very soluble in chloroform, the liniment made with it leaves nothing to be desired.
_Linimentum Plumbi Subacetatis_.–When liq. plumbi subacet. is mixed with cotton seed oil and allowed to stand for some time the oil assumes a reddish color similar to that of freshly made tincture of myrrh. When the liquor is mixed with olive oil, if the oil be pure, no such change takes place. Noticing this change, it occurred to me that this would be a simple and easy way to detect cotton seed oil when mixed with olive oil. This change usually takes place after standing from twelve to twenty-four hours. It is easily detected in mixtures containing five per cent., or even less, of the oils, and I am convinced, after making numerous experiments with different oils, that it is peculiar to cotton seed oil.–_American Journal of Pharmacy_.
* * * * *
THE FOOD AND ENERGY OF MAN.
[Footnote: From a lecture delivered at the Sanitary Congress, at Newcastle-on-Tyne, September 28, 1882.]
By PROF. DE CHAUMONT, F.R.S.
Although eating cannot be said to be in any way a new fashion, it has nevertheless been reserved for modern times, and indeed we may say the present generation, to get a fairly clear idea of the way in which food is really utilized for the work of our bodily frame. We must not, however, plume ourselves too much upon our superior knowledge, for inklings of the truth, more or less dim, have been had through all ages, and we are now stepping into the inheritance of times gone by, using the long and painful experience of our predecessors as the stepping-stone to our more accurate knowledge of the present time. In this, as in many other things, we are to some extent in the position of a dwarf on the shoulders of a giant; the dwarf may, indeed, see further than the giant; but he remains a dwarf, and the giant a giant.
The question has been much discussed as to what the original food of man was, and some people have made it a subject of excited contention. The most reasonable conclusion is that man is naturally a frugivorous or fruit-eating animal, like his cousins the monkeys, whom he still so much resembles. This forms a further argument in favor of his being originated in warm regions, where fruits of all kinds were plentiful. It is pretty clear that the resort to animal food, whether the result of the pressure of want from failure of vegetable products, or a mere taste and a desire for change and more appetizing food, is one that took place many ages ago, probably in the earliest anthropoid, if not in the latest pithecoid stage. No doubt some advantage was recognized in the more rapid digestion and the comparative ease with which the hunter or fisher could obtain food, instead of waiting for the ripening of fruits in countries which had more or less prolonged periods of cold and inclement weather. Some anatomical changes have doubtless resulted from the practice, but they are not of sufficiently marked character to found much argument upon; all that we can say being that the digestive apparatus in man seems well adapted for digesting any food that is capable of yielding nutriment, and that even when an entire change is made in the mode of feeding, the adaptability of the human system shows itself in a more or less rapid accommodation to the altered circumstances.
Food, then, is any substance which can be taken into the body and applied to use, either in building up or repairing the tissues and framework of the body itself, or in providing energy and producing animal heat, or any substance which, without performing those functions directly, controls, directs, or assists their performance. With this wide definition it is evident that we include all the ordinary articles recognized commonly as food, and that we reject all substances recognized commonly as poisons. But it will also include such substances as water and air, both of which are essential for nutrition, but are not usually recognized as belonging to the list of food substances in the ordinary sense. When we carry our investigation further, we find that the organic substances may be again divided into two distinct classes, namely, that which contains nitrogen (the casein), and those that do not (the butter and sugar).
On ascertaining this, we are immediately struck with the remarkable fact that all the tissues and fluids of the body, muscles (or flesh), bone, blood–all, in short, except the fat–contain nitrogen, and, consequently, for their building up in the young, and for their repair and renewal in the adult, nitrogen is absolutely required. We therefore reasonably infer that the nitrogenous substance is necessary for this purpose. Experiment has borne this out, for men who have been compelled to live without nitrogenous food by dire necessity, and criminals on whom the experiment has been tried, have all perished sooner or later in consequence. When nitrogenous substances are used in the body, they are, of course, broken up and oxidized, or perhaps we ought to say more accurately, they take the place of the tissues of the body which wear away and are carried off by oxidation and other chemical changes.
Now, modern science tell us that such changes are accompanied with manifestations of energy in some form or other, most frequently in that of heat, and we must look, therefore, upon nitrogenous food as contributing to the energy of the body in addition to its other functions.
What are the substances which we may class as nitrogenous. In the first place, we have the typical example of the purest form in _albumin_, or white of egg; and from this the name is now given to the class of _albuminates_. The animal albuminates are: Albumin from eggs, fibrin from muscles, or flesh, myosin, or synronin, also from animals, casein (or cheesy matter) from milk, and the nitrogenous substances from blood. In the vegetable kingdom, we have glutin, or vegetable fibrin, which is the nourishing constituent of wheat, barley, oats, etc.; and legumin, or vegetable casein, which is the peculiar substance found in peas and beans. The other organic constituents–viz., the fats and the starches and sugars–contain no nitrogen, and were at one time thought to be concerned in producing animal heat.
We now know–thanks to the labors of Joule, Lyon Playfair, Clausius, Tyndall, Helmholtz, etc.–that heat itself is a mode of motion, a form of convertible energy, which can be made to do useful or productive work, and be expressed in terms of actual work done. Modern experiment shows that all our energy is derived from that of food, and, in particular from the non-nitrogenous part of it, that is, the fat, starch, and sugar. The nutrition of man is best maintained when he is provided with a due admixture of all the four classes of aliment which we have mentioned, and not only that, but he is also better off if he has a variety of each class. Thus he may and ought to have albumen, fibrine, gluten, and casein among the albuminates, or at least two of them; butter and lard, or suet, or oil among the fats; starch of wheat, potato, rice, peas, etc., and cane-sugar, and milk-sugar among the carbo-hydrates. The salts cannot be replaced, so far as we know. Life may be maintained in fair vigor for some time on albuminates only, but this is done at the expense of the tissues, especially the fat of the body, and the end must soon come; with fat and carbo hydrates alone vigor may also be maintained for some time, at the expense of the tissues also, but the limit is a near one, In either of these cases we suppose sufficient water and salts to be provided.
We must now inquire into the quantities of food necessary; and this necessitates a little consideration of the way in which the work of the body is carried on. We must look upon the human body exactly as a machine; like an engine with which we are all so familiar. A certain amount of work requires to be done, say, a certain number of miles of distance to be traversed; we know that to do this a certain number of pounds, or hundredweights, or tons of coal must be put into the fire of the boiler in order to furnish the requisite amount of energy through the medium of steam. This amount of fuel must bear a certain proportion to the work, and also to the velocity with which it is done, so both quantity and time have to be accounted for.
No lecture on diet would be complete without a reference to the vexed question of alcohol. I am no teetotal advocate, and I repudiate the rubbish too often spouted from teetotal platforms, talk that is, perhaps, inseparable from the advocacy of a cause that imports a good deal of enthusiasm. I am at one, however, in recognizing the evils of excess, and would gladly hail their diminution. But I believe that alcohol properly used may be a comfort and a blessing, just as I know that improperly used it becomes a bane and a curse. But we are now concerned with it as an article of diet in relation to useful work, and it may be well to call attention markedly to the fact that its use in this way is very limited. The experiments of the late Dr. Parkes, made in our laboratory, at Netley, were conclusive on the point, that beyond an amount that would be represented by about one and a half to two pints of beer, alcohol no longer provided any convertible energy, and that, therefore, to take it in the belief that it did do so is an error. It may give a momentary stimulus in considerable doses, but this is invariably followed by a corresponding depression, and it is a maxim now generally followed, especially on service, never to give it before or during work. There are, of course, some persons who are better without it altogether, and so all moderation ought to be commended, if not enjoyed.
There are other beverages which are more useful than the alcoholic, as restoratives, and for support in fatigue. Tea and coffee are particularly good. Another excellent restorative is a weak solution of Liebig’s extract of meat, which has a remarkable power of removing fatigue. Perhaps one of the most useful and most easily obtainable is weak oatmeal gruel, either hot or cold. With regard to tobacco, it also has some value in lessening fatigue in those who are able to take it, but it may easily be carried to excess. Of it we may say, as of alcohol, that in moderation it seems harmless, and even useful to some extent, but, in excess, it is rank poison.
There is one other point which I must refer to, and which is especially interesting to a great seaport like this. This is the question of scurvy–a question of vital importance to a maritime nation. A paper lately issued by Mr. Thomas Gray, of the Board of Trade, discloses the regrettable fact that since 1873 there has been a serious falling off, the outbreaks of scurvy having again increased until they reached ninety-nine in 1881. This, Mr. Gray seems to think, is due to a neglect of varied food scales; but it may also very probably have arisen from the neglect of the regulation about lime-juice, either as to issue or quality, or both. But it is also a fact of very great importance that mere monotony of diet has a most serious effect upon health; variety of food is not merely a pandering to gourmandism or greed, but a real sanitary benefit, aiding digestion and assimilation. Our Board of Trade has nothing to do with the food scales of ships, but Mr. Gray hints that the Legislature will have to interfere unless shipowners look to it themselves. The ease with which preserved foods of all kinds can be obtained and carried now removes the last shadow of an excuse for backwardness in this matter, and in particular the provision of a large supply of potatoes, both fresh and dried, ought to be an unceasing care; this is done on board American ships, and to this is doubtless owing in a great part the healthiness of their crews. Scurvy in the present day is a disgrace to shipowners and masters; and if public opinion is insufficient to protect the seamen, the legislature will undoubtedly step in and do so.
And now let me close by pointing out that the study of this commonplace matter of eating and drinking opens out to us the conception of the grand unity of nature; since we see that the body of man differs in no way essentially from other natural combinations, but is subject to the same universal physical laws, in which there is no blindness, no variableness, no mere chance, and disobedience of which is followed as surely by retribution as even the keenest eschatologist might desire.
* * * * *
RATTLESNAKE POISON.
By HENRY H. CROFT.
Some time since, in a paper to which I am unfortunately unable to refer, a French chemist affirmed that the poisonous principle in snakes, or eliminated by snakes, was of the nature of an alkaloid, and gave a name to this class of bodies.
Mr. Pedler has shown that snake poison is destroyed or neutralized by means of platinic chloride, owing probably to the formation of an insoluble double platinic chloride, such as is formed with almost if not all alkaloids.
In this country (Texas) where rattlesnakes are very common, and persons camping out much exposed to their bites, a very favorite anecdote, or _remedia_ as the Mexicans cull it, is a strong solution of iodine in potassium iodide.[1]
[Footnote 1: The solution is applied as soon as possible to the wound, preferably enlarged, and a few drops taken internally. The common Mexican _remedia_ is the root of the _Agave virginica_ mashed or chewed and applied to the wound, while part is swallowed.
Great faith is placed in this root by all residents here, who are seldom I without it, but, I have had no experience of it myself; and the internal administration is no doubt useless.
Even the wild birds know of this root; the queer paisano (? ground woodpecker) which eats snakes, when wounded by a _vibora de cascabel_, runs into woods, digs up and eats a root of the agave, just like the mongoose; but more than that, goes back, polishes off his enemy, and eats him. This has been told me by Mexicans who, it may be remarked, are not _always_ reliable.]
I have had occasion to prove the efficacy of this mixture in two cases of _cascabel_ bites, one on a buck, the other on a dog; and it occurred to me that the same explanation of its action might be given as above for the platinum salt, viz., the formation of an insoluble iodo compound as with ordinary alkaloids if the snake poison really belongs to this class.
Having last evening killed a moderate sized rattlesnake–_Crotalus horridus_–which had not bitten anything, I found the gland fully charged with the white opaque poison; on adding iodine solution to a drop of this a dense light-brown precipitate was immediately formed, quite similar to that obtained with most alkaloids, exhibiting under the microscope no crystalline structure.
In the absence of iodine a good extemporaneous solution for testing alkaloids, and perhaps a snake poison antidote, may be made by adding a few drops of ferric chloride to solution of potassium of iodide; this is a very convenient test agent which I used in my laboratory for many years.
Although rattlesnake poison could be obtained here in very considerable quantity, it is out of my power to make such experiments as I could desire, being without any chemical appliances and living a hundred miles or more from any laboratory. The same may be said with regard to books, and possibly the above iodine reaction has been already described.
Dr. Richards states that the cobra poison is destroyed by potassium permanganate; but this is no argument in favor of that salt as an antidote. Mr. Pedler also refers to it, but allows that it would not be probably of any use after the poison had been absorbed. Of this I think there can be no doubt, remembering the easy decomposition of permanganate by most organic substances, and I cannot but think that the medicinal or therapeutic advantages of that salt, taken internally, are equally problematical, unless the action is supposed to take place in the stomach.
In the bladder of the same rattlesnake I found a considerable quantity of light-brown amorphous ammonium urate, the urine pale yellow.–_Chemical News_.
Hermanitas Ranch, Texas.
* * * * *
THE CHINESE SIGN MANUAL.
[Footnote: Dr. D. J. Macgowan, in Medical Reports of China. 1881.]
Two writers in _Nature_, both having for their theme “Skin-furrows on the Hand,” solicit information on the subject from China.[1] As the subject is considered to have a bearing on medical jurisprudence and ethnology as well, this report is a suitable vehicle for responding to the demand.
[Footnote 1: Henry Faulds, Tzukiyi Hospital, Tokio, Japan. W. J. Herschel, Oxford, England.–_Nature_, 28th October and 25th November, 1880.]
Dr. Faulds’ observations on the finger-tips of the Japanese have an ethnic bearing and relate to the subject of heredity. Mr. Herschel considers the subject as an agent of Government, he having charge for twenty years of registration offices in India, where he employed finger marks as sign manuals, the object being to prevent personation and repudiation. Doolittle, in his “Social Life of the Chinese,” describes the custom. I cannot now refer to native works where the practice of employing digital rugae as a sign manual is alluded to. I doubt if its employment in the courts is of ancient date. Well-informed natives think that it came into vogue subsequent to the Han period; if so, it is in Egypt that earliest evidence of the practice is to be found. Just as the Chinese courts now require criminals to sign confessions by impressing thereto the whorls of their thumb-tips–the right thumb in the case of women, the left in the case of men–so the ancient Egyptians, it is represented, required confessions to be sealed with their thumbnails–most likely the tip of the digit, as in China. Great importance is attached in the courts to this digital form of signature, “finger form.” Without a confession no criminal can be legally executed, and the confession to be valid must be attested by the thumb-print of the prisoner. No direct coercion is employed to secure this; a contumacious culprit may, however, be tortured until he performs the act which is a prerequisite to his execution. Digital signatures are sometimes required in the army to prevent personation; the general in command at Wenchow enforces it on all his troops. A document thus attested can no more be forged or repudiated than a photograph–not so easily, for while the period of half a lifetime effects great changes in the physiognomy, the rugae of the fingers present the same appearance from the cradle to the grave; time writes no wrinkles there. In the army everywhere, when the description of a person is written down, the relative number of volutes and coniferous finger-tips is noted. It is called taking the “whelk striae,” the fusiform being called “rice baskets,” and the volutes “peck measures.” A person unable to write, the form of signature which defies personation or repudiation is required in certain domestic cases, as in the sale of children or women. Often when a child is sold the parents affix their finger marks to the bill of sale; when a husband puts away his wife, giving her a bill of divorce, he marks the document with his entire palm; and when a wife is sold, the purchaser requires the seller to stamp the paper with hands and feet, the four organs duly smeared with ink. Professional fortune tellers in China take into account almost the entire system of the person whose future they attempt to forecast, and of course they include palmistry, but the rugae of the finger-ends do not receive much attention. Amateur fortune-tellers, however, discourse as glibly on them as phrenologists do of “bumps”–it is so easy. In children the relative number of volute and conical striae indicate their future. “If there are nine volutes,” says a proverb, “to one conical, the boy will attain distinction without toil.”
Regarded from an ethnological point of view, I can discover merely that the rugae of Chinamen’s fingers differ from Europeans’, but there is so little uniformity observable that they form no basis for distinction, and while the striae may be noteworthy points in certain medico-legal questions, heredity is not one of them.
* * * * *
LUCIDITY.
At the close of an interesting address lately delivered at the reopening of the Liverpool University College and School of Medicine, Mr. Matthew Arnold said if there was one word which he should like to plant in the memories of his audience, and to leave sticking there after he had gone, it was the word _lucidity_. If he had to fix upon the three great wants at this moment of the three principal nations of Europe, he should say that the great want of the French was morality, that the great want of the Germans was civil courage, and that our own great want was lucidity. Our own want was, of course, what concerned us the most. People were apt to remark the defects which accompanied certain qualities, and to think that the qualities could not be desirable because of the defects which they saw accompanying them. There was no greater and salutary lesson for men to learn than that a quality may be accompanied, naturally perhaps, by grave dangers; that it may actually present itself accompanied by terrible defects, and yet that it might itself be indispensable. Let him illustrate what he meant by an example, the force of which they would all readily feel. Seriousness was a quality of our nation. Perhaps seriousness was always accompanied by certain dangers. But, at any rate, many of our French neighbors would say that they found our seriousness accompanied by so many false ideas, so much prejudice, so much that was disagreeable, that it could not have the value which we attributed to it. And yet we knew that it was invaluable. Let them follow the same mode of reasoning as to the quality of lucidity. The French had a national turn for lucidity as we had a national turn for seriousness. Perhaps a national turn for lucidity carried with it always certain dangers. Be this as it might, it was certain that we saw in the French, along with their lucidity, a want of seriousness, a want of reverence, and other faults, which greatly displeased us. Many of us were inclined in consequence to undervalue their lucidity, or to deny that they had it. We were wrong: it existed as our seriousness existed; it was valuable as our seriousness was valuable. Both the one and the other were valuable, and in the end indispensable.
What was lucidity? It was negatively that the French have it, and he would therefore deal with its negative character merely. Negatively, lucidity was the perception of the want of truth and validness in notions long current, the perception that they are no longer possible, that their time is finished, and they can serve us no more. All through the last century a prodigious travail for lucidity was going forward in France. Its principal agent was a man whose name excited generally repulsion in England, Voltaire. Voltaire did a great deal of harm in France. But it was not by his lucidity that he did harm; he did it by his want of seriousness, his want of reverence, his want of sense for much that is deepest in human nature. But by his lucidity he did good.
All admired Luther. Conduct was three-fourths of life, and a man who worked for conduct, therefore, worked for more than a man who worked for intelligence. But having promised this, it might be said that the Luther of the eighteenth century and of the cultivated classes was Voltaire. As Luther had an antipathy to what was immoral, so Voltaire had an antipathy to what was absurd, and both of them made war upon the object of their antipathy with such masterly power, with so much conviction, so much energy, so much genius, that they carried their world with them–Luther his Protestant world, and Voltaire his French world–and the cultivated classes throughout the continent of Europe generally.
Voltaire had more than negative lucidity; he had the large and true conception that a number and equilibrium of activities were necessary for man. “_Il faut douner a notre ame toutes les formes possibles_” was a maxim which Voltaire really and truly applied in practice, “advancing,” as Michelet finely said of him, in every direction with a marvelous vigor and with that conquering ambition which Vico called _mens heroica_. Nevertheless. Voltaire’s signal characteristic was his lucidity, his negative lucidity.
There was a great and free intellectual movement in England in the eighteenth century–indeed, it was from England that it passed into France; but the English had not that strong natural bent for lucidity which the French had. Its bent was toward other things in preference. Our leading thinkers had not the genius and passion for lucidity which distinguished Voltaire. In their free inquiry they soon found themselves coming into collision with a number of established facts, beliefs, conventions. Thereupon all sorts of practical considerations began to sway them. The danger signal went up, they often stopped short, turned their eyes another way, or drew down a curtain between themselves and the light. “It seems highly probable,” said Voltaire, “that nature has made thinking a portion of the brain, as vegetation is a function of trees; that we think by the brain just as we walk by the feet.” So our reason, at least, would lead us to conclude, if the theologians did not assure us of the contrary; such, too, was the opinion of Locke, but he did not venture to announce it. The French Revolution came, England grew to abhor France, and was cut off from the Continent, did great things, gained much, but not in lucidity. The Continent was reopened, the century advanced, time and experience brought their lessons, lovers of free and clear thought, such as the late John Stuart Mill, arose among us. But we could not say that they had by any means founded among us the reign of lucidity.
Let them consider that movement of which we were hearing so much just now: let them look at the Salvation Army and its operations. They would see numbers, funds, energy, devotedness, excitement, conversions, and a total absence of lucidity. A little lucidity would make the whole movement impossible. That movement took for granted as its basis what was no longer possible or receivable; its adherents proceeded in all they did on the assumption that that basis was perfectly solid, and neither saw that it was not solid, nor ever even thought of asking themselves whether it was solid or not.
Taking a very different movement, and one of far higher dignity and import, they had all had before their minds lately the long-devoted, laborious, influential, pure, pathetic life of Dr. Pusey, which had just ended. Many of them had also been reading in the lively volumes of that acute, but not always good-natured rattle, Mr. Mozley, an account of that great movement which took from Dr. Pusey its earlier name. Of its later stage of Ritualism they had had in this country a now celebrated experience. This movement was full of interest. It had produced men to be respected, men to be admired, men to be beloved, men of learning, goodness, genius, and charm. But could they resist the truth that lucidity would have been fatal to it? The movers of all those questions about apostolical succession, church patristic authority, primitive usage, postures, vestments–questions so passionately debated, and on which he would not seek to cast ridicule–did not they all begin by taking for granted something no longer possible or receivable, build on this basis as if it were indubitably solid, and fail to see that their basis not being solid, all they built upon it was fantastic?
He would not say that negative lucidity was in itself a satisfactory possession, but he said that it was inevitable and indispensable, and that it was the condition of all serious construction for the future. Without it at present a man or a nation was intellectually and spiritually all abroad. If they saw it accompanied in France by much that they shrank from, they should reflect that in England it would have influences joined with it which it had not in France–the natural seriousness of the people, their sense of reverence and respect, their love for the past. Come it must; and here where it had been so late in coming, it would probably be for the first time seen to come without danger.
Capitals were natural centers of mental movement, and it was natural for the classes with most leisure, most freedom, most means of cultivation, and most conversance with the wide world to have lucidity though often they had it not. To generate a spirit of lucidity in provincial towns, and among the middle classes bound to a life of much routine and plunged in business, was more difficult. Schools and universities, with serious and disinterested studies, and connecting those studies the one with the other and continuing them into years of manhood, were in this case the best agency they could use. It might be slow, but it was sure. Such an agency they were now going to employ. Might it fulfill all their expectations! Might their students, in the words quoted just now, advance in every direction with a marvelous vigor, and with that conquering ambition which Vico called _mens heroica_! And among the many good results of this, might one result be the acquisition in their midst of that indispensable spirit–the spirit of lucidity!
* * * * *
ON SOME APPARATUS THAT PERMIT OF ENTERING FLAMES.
[Footnote: A. de Rochas in the _Revue Scientifique_.]
In the following notes I shall recall a few experiments that indicate under what conditions the human organism is permitted to remain unharmed amid flames. These experiments were published in England in 1882, in the twelfth letter from Brewster to Walter Scott on natural magic. They are, I believe, not much known in France, and possess a practical interest for those who are engaged in the art of combating fires.
At the end of the last century Humphry Davy observed that, on placing a very fine wire gauze over a flame, the latter was cooled to such a point that it could not traverse the meshes. This phenomenon, which he attributed to the conductivity and radiating power of the metal, he soon utilized in the construction of a lamp for miners.
Some years afterward Chevalier Aldini, of Milan, conceived the idea of making a new application of Davy’s discovery in the manufacture of an envelope that should permit a man to enter into the midst of flames. This envelope, which was made of metallic gauze with 1-25th of an inch meshes, was composed of five pieces, as follows: (1) a helmet, with mask, large enough, to allow a certain space between it and the internal bonnet of which I shall speak; (2) a cuirass with armlets; (3) a skirt for the lower part of the belly and the thighs; (4) a pair of boots formed of a double wire gauze; and (5) a shield five feet long by one and a half wide, formed of metallic gauze stretched over a light iron frame. Beneath this armor the experimenter was clad in breeches and a close coat of coarse cloth that had previously been soaked in a solution of alum. The head, hands, and feet were covered by envelopes of asbestos cloth whose fibers were about a half millimeter in diameter. The bonnet contained apertures for the eyes, nose, and ears, and consisted of a single thickness of fabric, as did the stockings, but the gloves were of double thickness, so that the wearer could seize burning objects with the hands.
Aldini, convinced of the services that his apparatus might render to humanity, traveled over Europe and gave gratuitous representations with it. The exercises generally took place in the following order: Aldini began by first wrapping his finger in asbestos and then with a double layer of wire gauze. He then held it for some instants in the flame of a candle or alcohol lamp. One of his assistants afterward put on the asbestos glove of which I have spoken, and, protecting the palm of his hand with another piece of asbestos cloth, seized a piece of red-hot iron from a furnace and slowly carried it to a distance of forty or fifty meters, lighted some straw with it, and then carried it back to the furnace. On other occasions, the experimenters, holding firebrands in their hands, walked for five minutes over a large grating under which fagots were burning.
In order to show how the head, eyes, and lungs were protected by the wire gauze apparatus, one of the experimenters put on the asbestos bonnet, helmet, and cuirass, and fixed the shield in front of his breast. Then, in a chafing dish placed on a level with his shoulder, a great fire of shavings was lighted, and care was taken to keep it up. Into the midst of these flames the experimenter then plunged his head and remained thus five or six minutes with his face turned toward them. In an exhibition given at Paris before a committee from the Academic des Sciences, there were set up two parallel fences formed of straw, connected by iron wire to light wicker work, and arranged so as to leave between them a passage 3 feet wide by 30 long. The heat was so intense, when the fences were set on fire, that no one could approach nearer than 20 or 25 feet; and the flames seemed to fill the whole space between them, and rose to a height of 9 or 10 feet. Six men clad in the Aldini suit went in, one behind the other, between the blazing fences, and walked slowly backward and forward in the narrow passage, while the fire was being fed with fresh combustibles from the exterior. One of these men carried on his back, in an ozier basket covered with wire gauze, a child eight years of age, who had on no other clothing than an asbestos bonnet. This same man, having the child with him, entered on another occasion a clear fire whose flames reached a height of 18 feet, and whose intensity was such that it could not be looked at. He remained therein so long that the spectators began to fear that he had succumbed; but he finally came out safe and sound.
One of the conclusions to be drawn from the facts just stated is that man can breathe in the midst of flames. This marvelous property cannot be attributed exclusively to the cooling of the air by its passage through the gauze before reaching the lungs; it shows also a very great resistance of our organs to the action of heat. The following, moreover, are direct proofs of such resistance. In England, in their first experiment, Messrs. Joseph Banks, Charles Blagden, and Dr. Solander remained for ten minutes in a hot-house whose temperature was 211 deg. Fahr., and their bodies preserved therein very nearly the usual heat. On breathing against a thermometer they caused the mercury to fall several degrees. Each expiration, especially when it was somewhat strong, produced in their nostrils an agreeable impression of coolness, and the same impression was also produced on their fingers when breathed upon. When they touched themselves their skin seemed to be as cold as that of a corpse; but contact with their watch chains caused them to experience a sensation like that of a burn. A thermometer placed under the tongue of one of the experimenters marked 98 deg. Fahr., which is the normal temperature of the human species.
Emboldened by these first results, Blagden entered a hot-house in which the thermometer in certain parts reached 262 deg. Fahr. He remained therein eight minutes, walked about in all directions, and stopped in the coolest part, which was at 240 deg. Fahr. During all this time he experienced no painful sensations; but, at the end of seven minutes, he felt an oppression of the lungs that inquieted him and caused him to leave the place. His pulse at that moment showed 144 beats to the minute, that is to say, double what it usually did. To ascertain whether there was any error in the indications of the thermometer, and to find out what effect would take place on inert substances exposed to the hot air that he had breathed, Blogden placed some eggs in a zinc plate in the hot-house, alongside the thermometer, and found that in twenty minutes they were baked hard.
A case is reported where workmen entered a furnace for drying moulds, in England, the temperature of which was 177 deg., and whose iron sole plate was so hot that it carbonized their wooden shoes. In the immediate vicinity of this furnace the temperature rose to 160 deg.. Persons not of the trade who approached anywhere near the furnace experienced pain in the eyes, nose, and ears.
A baker is cited in Angoumois, France, who spent ten minutes in a furnace at 132 deg. C.
The resistance of the human organism to so high temperatures can be attributed to several causes. First, it has been found that the quantity of carbonic acid exhaled by the lungs, and consequently the chemical phenomena of internal combustion that are a source of animal heat, diminish in measure as the external temperature rises. Hence, a conflict which has for result the retardation of the moment at which a living being will tend, without obstacle, to take the temperature of the surrounding medium. On another hand, it has been observed that man resists heat so much the less in proportion as the air is saturated with vapors. Dr. Berger, who supported for seven minutes a temperature varying from 109 deg. to 110 deg. C. in dry air, could remain only twelve minutes in a bagnio whose temperature rose from 41 deg. to 51.75 deg.. At the Hammam of Paris the highest temperature obtained is 87 deg., and Dr. E. Martin has not been able to remain therein more than five minutes. This physician reports that in 1743, the thermometer having exceeded 40 deg. at Pekin, 14,000 persons perished. These facts are explained by the cooling that the evaporation of perspiration produces on the surface of the body. Edwards has calculated that such evaporation is ten times greater in dry air in motion than in calm and humid air. The observations become still more striking when the skin is put in contact with a liquid or a solid which suppresses perspiration. Lemoine endured a bath of Bareges water of 37 deg. for half an hour; but at 45 deg. he could not remain in it more than seven minutes, and the perspiration began to flow at the end of six minutes. According to Brewster, persons who experience no malaise near a fire which communicates a temperature of 100 deg. C. to them, can hardly bear contact with alcohol and oil at 55 deg. and mercury at 48 deg..
The facts adduced permit us to understand how it was possible to bear one of the proofs to which it is said those were submitted who wished to be initiated into the Egyptian mysteries. In a vast vaulted chamber nearly a hundred feet long, there were erected two fences formed of posts, around which were wound branches of Arabian balm, Egyptian thorn, and tamarind–all very flexible and inflammable woods. When this was set on fire the flames arose as far as the vault, licked it, and gave the chamber the appearance of a hot furnace, the smoke escaping through pipes made for the purpose. Then the door was suddenly opened before the neophyte, and he was ordered to traverse this burning place, whose floor was composed of an incandescent grating.
The Abbe Terrason recounts all these details in his historic romance “Sethos,” printed at the end of last century. Unfortunately literary frauds were in fashion then, and the book, published as a translation of an old Greek manuscript, gives no indication of sources. I have sought in special works for the data which the abbe must have had as a basis, but I have not been able to find them. I suppose, however, that this description, which is so precise, is not merely a work of the imagination. The author goes so far as to give the dimensions of the grating (30 feet by 8), and, greatly embarrassed to explain how his hero was enabled to traverse it without being burned, is obliged to suppose it to have been formed of very thick bars, between which Sethos had care to place his feet. But this explanation is inadmissible. He who had the courage to rush, head bowed, into the midst of the flames, certainly would not have amused himself by choosing the place to put his feet. Braving the fire that surrounded his entire body, he must have had no other thought than that of reaching the end of his dangerous voyage as soon as possible. We cannot see very well, moreover, how this immense grate, lying on the ground, was raised to a red heat and kept at such a temperature. It is infinitely more simple to suppose that between the two fences there was a ditch sufficiently deep in which a fire had also been lighted, and which was covered by a grating as in the Aldini experiments. It is even probable that this grating was of copper, which, illuminated by the fireplace, must have presented a terrifying brilliancy, while in reality it served only to prevent the flames from the fireplace reaching him who dared to brave them.
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THE BUILDING STONE SUPPLY.
The use of stone as a building material was not resorted to, except to a trifling extent, in this country until long after the need of such a solid substance was felt. The early settler contented himself with the log cabin, the corduroy road, and the wooden bridge, and loose stone enough for foundation purposes could readily be gathered from the surface of the earth. Even after the desirability of more handsome and durable building material for public edifices in the colonial cities than wood became apparent, the ample resources which nature had afforded in this country were overlooked, and brick and stone were imported by the Dutch and English settlers from the Old World. Thus we find the colonists of the New Netherlands putting yellow brick on their list of non-dutiable imports in 1648; and such buildings in Boston as are described as being “fairly set forth with brick, tile, slate, and stone,” were thus provided only with foreign products. Isolated instances of quarrying stone are known to have occurred in the last century; but they are rare. The edifice known as “King’s Chapel,” Boston, erected in 1752, is the first one on record as being built from American stone; this was granite, brought from Braintree, Mass.
Granite is a rock particularly abundant in New England, though also found in lesser quantities elsewhere in this country. The first granite quarries that were extensively developed were those at Quincy, Mass., and work began at that point early in the present century. The fame of the stone became widespread, and it was sent to distant markets–even to New Orleans. The old Merchants’ Exchange in New York (afterward used as a custom house) the Astor House in that city, and the Custom House in New Orleans, all nearly or quite fifty years old, were constructed of Quincy granite, as were many other fine buildings along the Atlantic coast. In later years, not only isolated public edifices, but also whole blocks of stores, have been constructed of this material. It was from the Quincy quarries that the first railroad in this country was built; this was a horse-railroad, three miles long, extending to Neponset River, built in 1827.
Other points in Massachusetts have been famed for their excellent granite. After Maine was set off as a distinct State, Fox Island acquired repute for its granite, and built up an extensive traffic therein. Westerly, R.I., has also been engaged in quarrying this valuable rock for many years, most of its choicer specimens having been wrought for monumental purposes. Statues and other elaborate monumental designs are now extensively made therefrom. Smaller pieces and a coarser quality of the stone are here and elsewhere along the coast obtained in large quantities for the construction of massive breakwaters to protect harbors. Another point famous for its granite is Staten Island, New York. This stone weighs 180 pounds to the cubic foot, while the Quincy granite weighs but 165. The Staten Island product is used not only for building purposes, but is also especially esteemed for paving after both the Russ and Belgian patents. New York and other cities derive large supplies from this source. The granite of Weehawken, N.J., is of the same character, and greatly in demand. Port Deposit, Md., and Richmond, Va, are also centers of granite production. Near Abbeville, S.C., and in Georgia, granite is found quite like that of Quincy. Much southern granite, however, decomposes readily, and is almost as soft as clay. This variety of stone is found in great abundance in the Rocky Mountains; but, except to a slight extent in California, it is not yet quarried there.
Granite, having little grain, can be cut into blocks of almost any size and shape. Specimens as much as eighty feet long have been taken out and transported great distances. The quarrying is done by drilling a series of small holes, six inches or more deep and almost the same distance apart, inserting steel wedges along the whole line and then tapping each gently with a hammer in succession, in order that the strain may be evenly distributed.
A building material that came into use earlier than granite is known as freestone or sandstone; although its first employment does not date back further than the erection of King’s Chapel, Boston, already referred to as the earliest well-known occasion where granite was used in building. Altogether the most famous American sandstone quarries are those at Portland, on the Connecticut River, opposite Middletown. These were worked before the Revolution; and their product has been shipped to many distant points in the country. The long rows of “brownstone fronts” in New York city are mostly of Portland stone, though in many cases the walls are chiefly of brick covered with thin layers of the stone. The old red sandstone of the Connecticut valley is distinguished in geology for the discovery of gigantic fossil footprints of birds, first noticed in the Portland quarries in 1802. Some of these footprints measured ten to sixteen inches, and they were from four to six feet apart. The sandstone of Belleville, N.J., has also extensive use and reputation. Trinity Church in New York city and the Boston Atheneum are built of the product of these quarries; St. Lawrence County, New York, is noted also for a fine bed of sandstone. At Potsdam it is exposed to a depth of seventy feet. There are places though, in New England, New York, and Eastern Pennsylvania, where a depth of three hundred feet has been reached. The Potsdam sandstone is often split to the thinness of an inch. It hardens by exposure, and is often used for smelting furnace hearth-stones. Shawangunk Mountain, in Ulster County, yields a sandstone of inferior quality, which has been unsuccessfully tried for paving; as it wears very unevenly. From Ulster, Greene, and Albany Counties sandstone slabs for sidewalks are extensively quarried for city use; the principal outlets of these sections being Kingston, Saugerties, Coxsackie, Bristol, and New Baltimore, on the Hudson. In this region quantities amounting to millions of square feet are taken out in large sheets, which are often sawed into the sizes desired. The vicinity of Medina, in Western New York, yields a sandstone extensively used in that section for paving and curbing, and a little for building. A rather poor quality of this stone has been found along the Potomac, and some of it was used in the erection of the old Capitol building at Washington. Ohio yields a sandstone that is of a light gray color; Berea, Amherst, Vermilion, and Massillon are the chief points of production. St. Genevieve, Mo., yields a stone of fine grain of a light straw color, which is quite equal to the famous Caen stone of France. The Lake Superior sandstones are dark and coarse grained, but strong.
In some parts of the country, where neither granite nor sandstone is easily procured, blue and gray limestone are sometimes used for building, and, when hammer dressed, often look like granite. A serious objection to their use, however, is the occasional presence of iron, which rusts on exposure, and defaces the building. In Western New York they are widely used. Topeka stone, like the coquine of Florida and Bermuda, is soft like wood when first quarried, and easily wrought, but it hardens on exposure. The limestones of Canton, Mo., Joliet and Athens, Ill., Dayton, Sandusky, Marblehead, and other points in Ohio, Ellittsville, Ind., and Louisville and Bowling Green, Ky., are great favorites west. In many of these regions limestone is extensively used for macadamizing roads, for which it is excellently adapted. It also yields excellent slabs or flags for sidewalks.
One of the principal uses of this variety of stone is its conversion, by burning, into lime for building purposes. All limestones are by no means equally excellent in this regard. Thomaston lime, burned with Pennsylvania coal, near the Penobscot River, has had a wide reputation for nearly half a century. It has been shipped thence to all points along the Atlantic coast, invading Virginia as far as Lynchburg, and going even to New Orleans, Smithfield, R.I., and Westchester County, N.Y., near the lower end of the Highlands, also make a particularly excellent quality of lime. Kingston, in Ulster County, makes an inferior sort for agricultural purposes. The Ohio and other western stones yield a poor lime, and that section is almost entirely dependent on the east for supplies.
Marbles, like limestones, with which they are closely related, are very abundant in this country, and are also to be found in a great variety of colors. As early as 1804 American marble was used for statuary purposes. Early in the century it also obtained extensive employment for gravestones. Its use for building purposes has been more recent than granite and sandstone in this country; and it is coming to supersede the latter to a great degree. For mantels, fire-places, porch pillars, and like ornamental purposes, however, our variegated, rich colored and veined or brecciated marbles were in use some time before exterior walls were made from them. Among the earliest marble buildings were Girard College in Philadelphia and the old City Hall in New York, and the Custom House in the latter city, afterward used for a sub-treasury. The new Capitol building at Washington is among the more recent structures composed of this material. Our exports of marble to Cuba and elsewhere amount to over $300,000 annually, although we import nearly the same amount from Italy. And yet an article can be found in the United States fully as fine as the famous Carrara marble. We refer to that which comes from Rutland, Vt. This state yields the largest variety and choicest specimens. The marble belt runs both ways from Rutland County, where the only quality fit for statuary is obtained. Toward the north it deteriorates by growing less sound, though finer in grain; while to the south it becomes coarser. A beautiful black marble is obtained at Shoreham, Vt. There are also handsome brecciated marbles in the same state; and in the extreme northern part, near Lake Champlain, they become more variegated and rich in hue. Such other marble as is found in New England is of an inferior quality. The pillars of Girard College came from Berkshire, Mass., which ranks next after Vermont in reputation.
The marble belt extends from New England through New York, Pennsylvania, Maryland, the District of Columbia, and Virginia, Tennessee, and the Carolinas, to Georgia and Alabama. Some of the variegated and high colored varieties obtained near Knoxville, Tenn., nearly equal that of Vermont. The Rocky Mountains contain a vast abundance and variety.
Slate was known to exist in this country to a slight extent in colonial days. It was then used for gravestones, and to some extent for roofing and school purposes. But most of our supplies came from Wales. It is stated that a slate quarry was operated in Northampton County, Pa., as early as 1805. In 1826 James M. Porter and Samuel Taylor engaged in the business, obtaining their supplies from the Kittanninny Mountains. From this time the business developed rapidly, the village of Slateford being an outgrowth of it, and large rafts being employed to float the product down the Schuylkill to Philadelphia. By 1860 the industry had reached the capacity of 20,000 cases of slate, valued at $10 a case, annually. In 1839 quarries were opened in the Piscataquis River, forty miles north of Bangor, Me., but poor transportation facilities retarded the business. Vermont began to yield in 1852. New York’s quarries are confined to Washington County, near the Vermont line. Maryland has a limited supply from Harford County. The Huron Mountains, north of Marquette, Mich., contain slate, which is also said to exist in Pike County, Ga.
Grindstones, millstones, and whetstones are quarried in New York, Ohio, Michigan, Pennsylvania, and other States. Mica is found at Acworth and Grafton, N. H., and near Salt Lake, but our chief supply comes from Haywood, Yancey, Mitchell, and Macon counties, in North Carolina, and our product is so large that we can afford to export it. Other stones, such as silex, for making glass, etc., are found in profusion in various parts of the country, but we have no space to enter into a detailed account of them at present.–_Pottery and Glassware Reporter_.
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AN INDUSTRIAL REVOLUTION.
The most interesting change of which the Census gives account is the increase in the number of farms. The number has virtually doubled within twenty years. The population of the country has not increased in like proportion. A large part of the increase in number of farms has been due to the division of great estates. Nor has this occurred, as some may imagine, exclusively in the Southern States and the States to which immigration and migration have recently been directed. It is an important fact that the multiplication of farms has continued even in the older Northern States, though the change has not been as great in these as in States of the far West or the South. In New York there has been an increase of 25,000, or 11.5 per cent, in the number of farms since 1870; in New Jersey the increase has been 12.2 per cent., and in Pennsylvania 22.7 per cent., though the increase in population, and doubtless in the number of persons engaged in farming, has been much smaller. Ohio, Indiana, and Illinois also, have been considered fully settled States for years, at least in an agricultural point of view, and yet the number of farms has increased 26.1 per cent, in ten years in Ohio, 20.3 percent, in Indiana, and 26.1 per cent, in Illinois. The obvious explanation is that the growth of many cities and towns has created a market for a far greater supply of those products which may be most advantageously grown upon farms of moderate size; but even if this fully accounts for the phenomenon, the change must be recognized as one of the highest importance industrially, socially, and politically. The man who owns or rents and cultivates a farm stands on a very different footing from the laborer who works for wages. It is not a small matter that, in these six States alone, there are 205,000 more owners or managers of farms than there were only a decade ago.
As we go further toward the border, west or north, the influence of the settlement of new land is more distinctly felt. Even in Michigan, where new railroads have opened new regions to settlement, the increase in number of farms has been over 55 per cent. In Wisconsin, though the increase in railroad mileage has been about the same as in Michigan, the reported increase in number of farms has been only 28 per cent., but in Iowa it rises to 60 per cent., and in Minnesota to nearly 100 per cent. In Kansas the number of farms is 138,561, against 38,202 in 1870; in Nebraska 63,387, against 12,301; and in Dakota 17,435, against 1,720. In these regions the process is one of creation of new States rather than a change in the social and industrial condition of the population.
Some Southern States have gained largely, but the increase in these, though very great, is less surprising than the new States of the Northwest. The prevailing tendency of Southern agriculture to large farms and the employment of many hands is especially felt in States where land is still abundant. The greatest increase is in Texas, where 174,184 farms are reported, against 61,125 in 1870; in Florida, with 23,438 farms, against 10,241 in 1870; and in Arkansas, with 94,433 farms, against 49,424 in 1870. In Missouri 215,575 farms are reported, against 148,228 in 1870. In these States, though social changes have been great, the increase in number of farms has been largely due to new settlements, as in the States of the far Northwest. But the change in the older Southern States is of a different character.
Virginia, for example, has long been settled, and had 77,000 farms thirty years ago. But the increase in number within the past ten years has been 44,668, or 60.5 per cent. Contrasting this with the increase in New York, a remarkable difference appears. West Virginia had few more farms ten years ago than New Jersey; now it has nearly twice as many, and has gained in number nearly 60 per cent. North Carolina, too, has increased 78 per cent. in number of farms since 1870, and South Carolina 80 per cent. In Georgia the increase has been still greater–from 69,956 to 138,626, or nearly 100 per cent. In Alabama there are 135,864 farms, against 67,382 in 1870, an increase of over 100 per cent. These proportions, contrasted with those for the older Northern States, reveal a change that is nothing less than an industrial revolution. But the force of this tendency to division of estates has been greatest in the States named. Whereas the ratio of increase in number of farms becomes greater in Northern States as we go from the East toward the Mississippi River, at the South it is much smaller in Kentucky, Tennessee, Mississippi, and Louisiana than in the older States on the Atlantic coast. Thus in Louisiana the increase has been from 28,481 to 48,292 farms, or 70 per cent., and in Mississippi from 68,023 to 101,772 farms, or less than 50 per cent., against 100 in Alabama and Georgia. In Kentucky the increase has been from 118,422 to 166,453 farms, or 40 per cent., and in Tennessee from 118,141 to 165,650 farms, or 40 per cent., against 60 in Virginia and West Virginia, and 78 in North Carolina. Thus, while the tendency to division is far greater than in the Northern States of corresponding age, it is found in full force only in six of the older Southern States, Alabama, West Virginia, and four on the Atlantic coast. In these, the revolution already effected foreshadows and will almost certainly bring about important political changes within a few years. In these six States there 310,795 more farm owners or occupants than there were ten years ago.–_N.Y. Tribune_.
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A FARMER’S LIME KILN.
For information about burning lime we republish the following article furnished by a correspondent of the _Country Gentleman_ several years ago:
[Illustration: Fig. 1. Fig. 2. Fig. 3. A (Fig. 1), Railway Track–B B B, Iron Rods running through Kiln–C, Capstone over Arch–D, Arch–E, Well without brick or ash lining.]
I send you a description and sketch of a lime-kiln put up on my premises about five years ago. The dimensions of this kiln are 13 feet square by 25 feet high from foundation, and its capacity 100 bushels in 24 hours. It was constructed of the limestone quarried on the spot. It has round iron rods (shown in sketch) passing through, with iron plates fastened to the ends as clamps to make it more firm; the pair nearest the top should be not less than 2 feet from that point, the others interspersed about 2 feet apart–the greatest strain being near the top. The arch should be 7 feet high by 51/2 wide in front, with a gather on the top and sides of about 1 foot, with plank floor; and if this has a little incline it will facilitate shoveling the lime when drawn. The arch should have a strong capstone; also one immediately under the well of the kiln, with a hole 2 feet in diameter to draw the lime through; or two may be used with semicircle cut in each. Iron bars 2 inches wide by 1/8 inch thick are used in this kiln for closing it, working in slots fastened to capstone. These slots must be put in before the caps are laid. When it is desired to draw lime, these bars may be pushed laterally in the slots, or drawn out entirely, according to circumstances; 3 bars will be enough. The slots are made of iron bars 11/2 inches wide, with ends rounded and turned up, and inserted in holes drilled through capstone and keyed above.
The well of the kiln is lined with fire-brick one course thick, with a stratum of coal ashes three inches thick tamped in between the brick and wall, which proves a great protection to the wall. About 2,000 fire-bricks were used. The proprietors of this kiln say about one-half the lower part of the well might have been lined with a first quality of common brick and saved some expense and been just as good. The form of the well shown in Fig. 3 is 7 feet in diameter in the bilge, exclusive of the lining of brick and ashes. Experiments in this vicinity have proved this to be the best, this contraction toward the top being absolutely necessary, the expansion of the stone by the heat is so great that the lime cannot be drawn from perpendicular walls, as was demonstrated in one instance near here, where a kiln was built on that principle. The kiln, of course, is for coal, and our stone requires about three-quarters of a ton per 100 bushels of lime, but this, I am told, varies according to quality, some requiring more than others; the quantity can best be determined by experimenting; also the regulation of the heat–if too great it will cause the stones to melt or run together as it were, or, if too little, they will not be properly burned. The business requires skill and judgment to run it successfully.
This kiln is located at the foot of a steep bluff, the top about level with the top of the kiln, with railway track built of wooden sleepers, with light iron bars, running from the bluff to the top of the kiln, and a hand-car makes it very convenient filling the kiln. Such a location should be had if possible. Your inquirer may perhaps get some ideas of the principles of a kiln for using _coal_. The dimensions may be reduced, if desired. If for _wood_, the arch would have to be formed for that, and the height of kiln reduced.
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THE MANUFACTURE OF APPLE JELLY.
[Footnote: From the report of the New York Agricultural Society.]
Within the county of Oswego, New York, Dewitt C. Peck reports there are five apple jelly factories in operation. The failure of the apple crop, for some singular and unexplained reason, does not extend in great degree to the natural or ungrafted fruit. Though not so many as common, even of these apples, there are yet enough to keep these five mills and the numerous cider mills pretty well employed. The largest jelly factory is located near the village of Mexico, and as there are some features in regard to this manufacture peculiar to this establishment which may be new and interesting, we will undertake a brief description. The factory is located on the Salmon Creek, which affords the necessary power. A portion of the main floor, first story, is occupied as a saw mill, the slabs furnishing fuel for the boiler furnace connected with the evaporating department. Just above the mill, along the bank of the pond, and with one end projecting over the water, are arranged eight large bins, holding from five hundred to one thousand bushels each, into which the apples are delivered from the teams. The floor in each of these has a sharp pitch or inclination toward the water and at the lower end is a grate through which the fruit is discharged, when wanted, into a trough half submerged in the pond.
The preparation of the fruit and extraction of the juice proceeds as follows: Upon hoisting a gate in the lower end of this trough, considerable current is caused, and the water carries the fruit a distance of from thirty to one hundred feet, and passes into the basement of the mill, where, tumbling down a four-foot perpendicular fall, into a tank, tight in its lower half and slatted so as to permit the escape of water and impurities in the upper half, the apples are thoroughly cleansed from all earthy or extraneous matter. Such is the friction caused by the concussion of the fall, the rolling and rubbing of the apples together, and the pouring of the water, that decayed sections of the fruit are ground off and the rotten pulp passes away with other impurities. From this tank the apples are hoisted upon an endless chain elevator, with buckets in the form of a rake-head with iron teeth, permitting drainage and escape of water, to an upper story of the mill, whence by gravity they descend to the grater. The press is wholly of iron, all its motions, even to the turning of the screws, being actuated by the water power. The cheese is built up with layers inclosed in strong cotton cloth, which displaces the straw used in olden time, and serves also to strain the cider. As it is expressed from the press tank, the cider passes to a storage tank, and thence to the defecator.
This defecator is a copper pan, eleven feet long and about three feet wide. At each end of this pan is placed a copper tube three inches in diameter and closed at both ends. Lying between and connecting these two, are twelve tubes, also of copper, 11/2 inches in diameter, penetrating the larger tubes at equal distances from their upper and under surfaces, the smaller being parallel with each other, and 11/2 inches apart. When placed in position, the larger tubes, which act as manifolds, supplying the smaller with steam, rest upon the bottom of the pan, and thus the smaller pipes have a space of three-fourths of an inch underneath their outer surfaces.
The cider comes from the storage tank in a continuous stream about three-eighths of an inch in diameter. Steam is introduced to the large or manifold tubes, and from them distributed through the smaller ones at a pressure of from twenty-five to thirty pounds per inch. Trap valves are provided for the escape of water formed by condensation within the pipes. The primary object of the defecator is to remove all impurities and perfectly clarify the liquid passing through it. All portions of pomace and other minute particles of foreign matter, when heated, expand and float in the form of scum upon the surface of the cider. An ingeniously contrived floating rake drags off this scum and delivers it over the side of the pan. To facilitate this removal, one side of the pan, commencing at a point just below the surface of the cider, is curved gently outward and upward, terminating in a slightly inclined plane, over the edge of which the scum is pushed by the rake into a trough and carried away. A secondary purpose served by the defecator is that of reducing the cider by evaporation to a partial sirup of the specific gravity of about 20 deg. Baume. When of this consistency the liquid is drawn from the bottom and less agitated portion of the defecator by a siphon, and thence carried to the evaporator, which is located upon the same framework and just below the defecator.
The evaporator consists of a separate system of six copper tubes, each twelve feet long and three inches in diameter. These are each jacketed or inclosed in an iron pipe of four inches internal diameter, fitted with steam-tight collars so as to leave half an inch steam space surrounding the copper tubes. The latter are open at both ends permitting the admission and egress of the sirup and the escape of the steam caused by evaporation therefrom, and are arranged upon the frame so as to have a very slight inclination downward in the direction of the current, and each nearly underneath its predecessor in regular succession. Each is connected by an iron supply pipe, having a steam gauge or indicator attached, with a large manifold, and that by other pipes with a steam boiler of thirty horse power capacity. Steam being let on at from twenty five to thirty pounds pressure, the stream of sirup is received from the defecator through a strainer, which removes any impurities possibly remaining into the upper evaporator tube; passing in a gentle flow through that, it is delivered into a funnel connected with the next tube below, and so, back and forth, through the whole system. The sirup enters the evaporator at a consistency of from 20 deg. to 23 deg. Baume, and emerges from the last tube some three minutes later at a consistency of from 30 deg. to 32 deg. Baume, which is found on cooling to be the proper point for perfect jelly. This point is found to vary one or two degrees, according to the fermentation consequent upon bruises in handling the fruit, decay of the same, or any little delay in expressing the juice from the cheese. The least fermentation occasions the necessity for a lower reduction. To guard against this, no cheese is allowed to stand over night, no pomace left in the grater or vat, no cider in the tank; and further to provide against fermentation, a large water tank is located upon the roof and filled by a force pump, and by means of hose connected with this, each grater, press, vat, tank, pipe, trough, or other article of machinery used, can be thoroughly washed and cleansed. Hot water, instead of cider, is sometimes sent through the defecator, evaporator, etc., until all are thoroughly scalded and purified. If the saccharometer shows too great or too little reduction, the matter is easily regulated by varying the steam pressure in the evaporator by means of a valve in the supply pipe. If boiled cider instead of jelly is wanted for making pies, sauces, etc., it is drawn off from one of the upper evaporator tubes according to the consistency desired; or can be produced at the end of the process by simply reducing the steam pressure.
As the jelly emerges from the evaporator it is transferred to a tub holding some fifty gallons, and by mixing a little therein, any little variations in reduction or in the sweetness or sourness of the fruit used are equalized. From this it is drawn through faucets, while hot, into the various packages in which it is shipped to market. A favorite form of package for family use is a nicely turned little wooden bucket with cover and bail, two sizes, holding five and ten pounds respectively. The smaller packages are shipped in cases for convenience in handling. The present product of this manufactory is from 1,500 to 1,800 pounds of jelly each day of ten hours. It is calculated that improvements now in progress will increase this to something more than a ton per day. Each bushel of fruit will produce from four to five pounds of jelly, fruit ripening late in the season being more productive than earlier varieties. Crab apples produce the finest jelly; sour, crabbed, natural fruit makes the best looking article, and a mixture of all varieties gives most satisfactory results as to flavor and general quality.
As the pomace is shoveled from the finished cheese, it is again ground under a toothed cylinder, and thence drops into large troughs, through a succession of which a considerable stream of water is flowing. Here it is occasionally agitated by raking from the lower to the upper end of the trough as the current carries it downward, and the apple seeds becoming disengaged drop to the bottom into still water, while the pulp floats away upon the stream. A succession of troughs serves to remove nearly all the seeds. The value of the apple seeds thus saved is sufficient to pay the daily wages of all the hands employed in the whole establishment. The apples are measured in the wagon box, one and a half cubic feet being accounted a bushel.
This mill ordinarily employs about six men: One general superintendent, who buys and measures the apples, keeps time books, attends to all the accounts and the working details of the mill, and acts as cashier; one sawyer, who manufactures lumber for the local market and saws the slabs into short lengths suitable for the furnace; one cider maker, who grinds the apples and attends the presses; one jelly maker, who attends the defecator, evaporator, and mixing tub, besides acting as his own fireman and engineer; one who attends the apple seed troughs and acts as general helper, and one man-of-all-work to pack, ship and assist whenever needed. The establishment was erected late in the season of 1880, and manufactured that year about forty-five tons of jelly, besides considerable cider exchanged to the farmers for apples, and some boiled cider.
The price paid for apples in 1880, when the crop was superabundant, was six to eight cents per bushel; in 1881, fifteen cents. The proprietor hopes next year to consume 100,000 bushels. These institutions are important to the farmer in that they use much fruit not otherwise valuable and very perishable. Fruit so crabbed and gnarled as to have no market value, and even frozen apples, if delivered while yet solid, can be used. (Such apples are placed in the water while frozen, the water draws the frost sufficiently to be grated, and passing through the press and evaporator before there is time for chemical change, they are found to make very good jelly. They are valuable to the consumer by converting the perishable, cheap, almost worthless crop of the bearing and abundant years into such enduring form that its consumption may be carried over to years of scarcity and furnish healthful food in cheap and pleasant form to many who would otherwise be deprived; and lastly, they are of great interest to society, in that they give to cider twice the value for purposes of food that it has or can have, even to the manufacturer, for use as a beverage and intoxicant.
* * * * *
IMPROVED GRAPE BAGS.
It stands to reason that were our summers warmer we should be able to grow grapes successfully on open walls; it is therefore probable that a new grape bag, the invention of M. Pelletier, 20 Rue de la Banque, Paris, intended to serve a double purpose, viz., protecting the fruit and hastening its maturity, will, when it becomes known, be welcomed in this country. It consists of a square of curved glass so fixed to the bag that the sun’s rays are concentrated upon the fruit, thereby rendering its ripening more certain in addition to improving its quality generally. The glass is affixed to the bag by means of a light iron wire support. It covers that portion of it next the sun, so that it increases the amount of light and warms the grapes without scorching them, a result due to the convexity of the glass and the layer of air between it and the bag. M. Pelletier had the idea of rendering these bags cheaper by employing plain squares instead of curved ones, but the advantage thus obtained was more than counterbalanced by their comparative inefficacy. In practice it was found that the curved squares gave an average of 7 deg. more than the straight ones, while there was a difference of 10 deg. when the bags alone were used, thus plainly demonstrating the practical value of the invention.
Whether these glass-fronted bags would have much value in the case of grapes grown under glass in the ordinary way is a question that can only be determined by actual experiment; but where the vines are on walls, either under glass screens or in the open air, so that the bunches feel the full force of the sun’s rays, there can be no doubt as to their utility, and it is probable that by their aid many of the continental varieties which we do not now attempt to grow in the open, and which are scarcely worthy of a place under glass, might be well ripened. At any rate we ought to give anything a fair trial which may serve to neutralize, if only in a slight degree, the uncertainty of our summers. As it is, we have only about two varieties of grapes, and these not the best of the hardy kinds, as regards flavor and appearance, that ripen out of doors, and even these do not always succeed. We know next to nothing of the many really well-flavored kinds which are so much appreciated in many parts of the Continent. The fact is, our outdoor culture of grapes offers a striking contrast to that practiced under glass, and although our comparatively sunless and moist climate affords some excuse for our shortcomings in this respect, there is no valid reason for the utter want of good culture which is to be observed in a general way.
[Illustration: GRAPE BAG.–OPEN.]
Given intelligent training, constant care in stopping the laterals, and checking mildew as well as thinning the berries, allowing each bunch to get the full benefit of sun and air, and I believe good eatable grapes would often be obtained even in summers marked by a low average temperature.
[Illustration: GRAPE BAG.–CLOSED.]
If, moreover, to a good system of culture we add some such mechanical contrivance as that under notice whereby the bunches enjoy an average warmth some 10 deg. higher than they otherwise would do, we not only insure the grapes coming to perfection in favored districts, but outdoor culture might probably be practiced in higher latitudes than is now practicable.
[Illustration: CURVED GLASS FOR FRONT OF BAG.]
The improved grape bag would also offer great facilities for destroying mildew or guarantee the grapes against its attacks, as a light dusting administered as soon as the berries were fairly formed would suffice for the season, as owing to the glass protecting the berries from driving rains, which often accompany south or south-west winds in summer and autumn, the sulphur would not be washed off.
[Illustration: CURVED GLASS FIXED ON BAG.]
The inventor claims, and we should say with just reason, that these glass fronted bags would be found equally serviceable for the ripening of pears and other choice fruits, and with a view to their being employed for such a purpose, he has had them made of varying sizes and shapes. In conclusion, it may be observed that, in addition to advancing the maturity of the fruits to which they are applied, they also serve to preserve them from falling to the ground when ripe.–J. COBNHILL, _in the Garden_.
* * * * *
UTILIZATION OF SOLAR HEAT.
At a popular fete in the Tuileries Gardens I was struck with an experiment which seems deserving of the immediate attention of the English public and military authorities.
Among the attractions of the fete was an apparatus for the concentration and utilization of solar heat, and, though the sun was not very brilliant, I saw this apparatus set in motion a printing machine which printed several thousand copies of a specimen newspaper entitled the _Soleil Journal_.
The sun’s rays are concentrated in a reflector, which moves at the same rate as the sun and heats a vertical boiler, setting the motive steam-engine at work. As may be supposed, the only object was to demonstrate the possibility of utilizing the concentrated heat of the solar rays; but I closely examined it, because the apparatus seems capable of great utility in existing circumstances. Here in France, indeed, there is a radical drawback–the sun is often overclouded.
Thousands of years ago the idea of utilizing the solar rays must have suggested itself, and there are still savage tribes who know no other mode of combustion; but the scientific application has hitherto been lacking. This void this apparatus will fill up. About fifteen years ago Professor Mouchon, of Tours, began constructing such an apparatus, and his experiments have been continued by M. Pifre, who has devoted much labor and expense to realizing M. Mouchou’s idea. A company has now come to his aid, and has constructed a number of apparatus of different sizes at a factory which might speedily turn out a large number of them. It is evident that in a country of uninterrupted sunshine the boiler might be heated in thirty or forty minutes. A portable apparatus could boil two and one-half quarts an hour, or, say, four gallons a day, thus supplying by distillation or ebullition six or eight men. The apparatus can be easily carried on a man’s back, and on condition of water, even of the worst quality, being obtainable, good drinking and cooking water is insured. M. De Rougaumond, a young scientific writer, has just published an interesting volume on the invention. I was able yesterday to verify his statements, for I saw cider made, a pump set in motion, and coffee made–in short, the calorific action of the sun superseding that of fuel. The apparatus, no doubt, has not yet reached perfection, but as it is it would enable the soldier in India or Egypt to procure in the field good water and to cook his food rapidly. The invention is of especial importance to England just now, but even when the Egyptian question is settled the Indian troops might find it of inestimable value.
Red tape should for once be disregarded, and a competent commission forthwith sent to 30 Rue d’Assas, with instructions to report immediately, for every minute saved may avoid suffering for Englishmen fighting abroad for their country. I may, of course, be mistaken, but a commission would decide, and if the apparatus is good the slightest delay in its adoption would be deplorable.–_Paris Correspondence London Times_.
* * * * *
HOW TO ESTABLISH A TRUE MERIDIAN.
[Footnote: A paper read before the Engineers’ Club of Philadelphia.]
By PROFESSOR L. M. HAUPT.
INTRODUCTORY.
The discovery of the magnetic needle was a boon to mankind, and has been of inestimable service in guiding the mariner through trackless waters, and the explorer over desert wastes. In these, its legitimate uses, the needle has not a rival, but all efforts to apply it to the accurate determination of permanent boundary lines have proven very unsatisfactory, and have given rise to much litigation, acerbity, and even death.
For these and other cogent reasons, strenuous efforts are being made to dispense, so far as practicable, with the use of the magnetic needle in surveying, and to substitute therefor the more accurate method of traversing from a true meridian. This method, however, involves a greater degree of preparation and higher qualifications than are generally possessed, and unless the matter can be so simplified as to be readily understood, it is unreasonable to expect its general application in practice.
Much has been written upon the various methods of determining, the true meridian, but it is so intimately related to the determination of latitude and time, and these latter in turn upon the fixing of a true meridian, that the novice can find neither beginning nor end. When to these difficulties are added the corrections for parallax, refraction, instrumental errors, personal equation, and the determination of the probable error, he is hopelessly confused, and when he learns that time may be sidereal, mean solar, local, Greenwich, or Washington, and he is referred to an ephemeris and table of logarithms for data, he becomes lost in “confusion worse confounded,” and gives up in despair, settling down to the conviction that the simple method of compass surveying is the best after all, even if not the most accurate.
Having received numerous requests for information upon the subject, I have thought it expedient to endeavor to prepare a description of the method of determining the true meridian which should be sufficiently clear and practical to be generally understood by those desiring to make use of such information.
This will involve an elementary treatment of the subject, beginning with the
DEFINITIONS.
The _celestial sphere_ is that imaginary surface upon which all celestial objects are projected. Its radius is infinite.
The _earth’s axis_ is the imaginary line about which it revolves.
The _poles_ are the points in which the axis pierces the surface of the earth, or of the celestial sphere.
A _meridian_ is a great circle of the earth cut out by a plane passing through the axis. All meridians are therefore north and south lines passing through the poles.
From these definitions it follows that if there were a star exactly at the pole it would only be necessary to set up an instrument and take a bearing to it for the meridian. Such not being the case, however, we are obliged to take some one of the near circumpolar stars as our object, and correct the observation according to its angular distance from the meridian at the time of observation.
For convenience, the bright star known as Ursae Minoris or Polaris, is generally selected. This star apparently revolves about the north pole, in an orbit whose mean radius is 1 deg. 19′ 13″,[1] making the revolution in 23 hours 56 minutes.
[Footnote 1: This is the codeclination as given in the Nautical Almanac. The mean value decreases by about 20 seconds each year.]
During this time it must therefore cross the meridian twice, once above the pole and once below; the former is called the _upper_, and the latter the _lower meridian transit or culmination_. It must also pass through the points farthest east and west from the meridian. The former is called the _eastern elongation_, the latter the _western_.
An observation may he made upon Polaris at any of these four points, or at any other point of its orbit, but this latter case becomes too complicated for ordinary practice, and is therefore not considered.
If the observation were made upon the star at the time of its upper or lower culmination, it would give the true meridian at once, but this involves a knowledge of the true local time of transit, or the longitude of the place of observation, which is generally an unknown quantity; and moreover, as the star is then moving east or west, or at right angles to the place of the meridian, at the rate of 15 deg. of arc in about one hour, an error of so slight a quantity as only four seconds of time would introduce an error of one minute of arc. If the observation be made, however, upon either elongation, when the star is moving up or down, that is, in the direction of the vertical wire of the instrument, the error of observation in the angle between it and the pole will be inappreciable. This is, therefore, the best position upon which to make the observation, as the precise time of the elongation need not be given. It can be determined with sufficient accuracy by a glance at the relative positions of the star Alioth, in the handle of the Dipper, and Polaris (see Fig. 1). When the line joining these two stars is horizontal or nearly so, and Alioth is to the _west_ of Polaris, the latter is at its _eastern_ elongation, and _vice versa_, thus:
[Illustration]
But since the star at either elongation is off the meridian, it will be necessary to determine the angle at the place of observation to be turned off on the instrument to bring it into the meridian. This angle, called the azimuth of the pole star, varies with the latitude of the observer, as will appear from Fig 2, and hence its value must be computed for different latitudes, and the surveyor must know his _latitude_ before he can apply it. Let N be the north pole of the celestial sphere; S, the position of Polaris at its eastern elongation; then N S=1 deg. 19′ 13″, a constant quantity. The azimuth of Polaris at the latitude 40 deg. north is represented by the angle N O S, and that at 60 deg. north, by the angle N O’ S, which is greater, being an exterior angle of the triangle, O S O. From this we see that the azimuth varies at the latitude.
We have first, then, to _find the latitude of the place of observation_.
Of the several methods for doing this, we shall select the simplest, preceding it by a few definitions.
A _normal_ line is the one joining the point directly overhead, called the _zenith_, with the one under foot called the _nadir_.
The _celestial horizon_ is the intersection of the celestial sphere by a plane passing through the center of the earth and perpendicular to the normal.
A _vertical circle_ is one whose plane is perpendicular to the horizon, hence all such circles must pass through the normal and have the zenith and nadir points for their poles. The _altitude_ of a celestial object is its distance above the horizon measured on the arc of a vertical circle. As the distance from the horizon to the zenith is 90 deg., the difference, or _complement_ of the altitude, is called the _zenith distance_, or _co-altitude_.
The _azimuth_ of an object is the angle between the vertical plane through the object and the plane of the meridian, measured on the horizon, and usually read from the south point, as 0 deg., through west, at 90, north 180 deg., etc., closing on south at 0 deg. or 360 deg..
These two co-ordinates, the altitude and azimuth, will determine the position of any object with reference to the observer’s place. The latter’s position is usually given by his latitude and longitude referred to the equator and some standard meridian as co-ordinates.
The _latitude_ being the angular distance north or south of the equator, and the _longitude_ east or west of the assumed meridian.
We are now prepared to prove that _the altitude of the pole is equal to the latitude of the place of observation_.
Let H P Z Q, etc., Fig. 2, represent a meridian section of the sphere, in which P is the north pole and Z the place of observation, then H H will be the horizon, Q Q the equator, H P will be the altitude of P, and Q Z the latitude of Z. These two arcs are equal, for H C Z = P C Q = 90 deg., and if from these equal quadrants the common angle P C Z be subtracted, the remainders H C P and Z C Q, will be equal.
To _determine the altitude of the pole_, or, in other words, _the latitude of the place_.
Observe the altitude of the pole star _when on the meridian_, either above or below the pole, and from this observed altitude corrected for refraction, subtract the distance of the star from the pole, or its _polar distance_, if it was an upper transit, or add it if a lower. The result will be the required latitude with sufficient accuracy for ordinary purposes.
The time of the star’s being on the meridian can be determined with sufficient accuracy by a mere inspection of the heavens. The refraction is _always negative_, and may be taken from the table appended by looking up the amount set opposite the observed altitude. Thus, if the observer’s altitude should be 40 deg. 39′ the nearest refraction 01′ 07″, should be subtracted from 40 deg. 37′ 00″, leaving 40 deg. 37′ 53″ for the latitude.
TO FIND THE AZIMUTH OF POLARIS.
As we have shown the azimuth of Polaris to be a function of the latitude, and as the latitude is now known, we may proceed to find the required azimuth. For this purpose we have a right-angled spherical triangle, Z S P, Fig. 4, in which Z is the place of observation, P the north pole, and S is Polaris. In this triangle we have given the polar distance, P S = 10 deg. 19′ 13″; the angle at S = 90 deg.; and the distance Z P, being the complement of the latitude as found above, or 90 deg.–L. Substituting these in the formula for the azimuth, we will have sin. Z = sin. P S / sin P Z or sin. of Polar distance / sin. of co-latitude, from which, by assuming different values for the co-latitude, we compute the following table:
AZIMUTH TABLE FOR POINTS BETWEEN 26 deg. and 50 deg. N. LAT.
LATTITUDES
___________________________________________________________________ | | | | | | | | | Year | 26 deg. | 28 deg. | 30 deg. | 32 deg. | 34 deg. | 36 deg. | |______|_________|__________|_________|_________|_________|_________| | | | | | | | | | | deg. ‘ ” | deg. ‘ ” | deg. ‘ ” | deg. ‘ ” | deg. ‘ ” | deg. ‘ ” | | 1882 | 1 28 05 | 1 29 40 | 1 31 25 | 1 33 22 | 1 35 30 | 1 37 52 | | 1883 | 1 27 45 | 1 29 20 | 1 31 04 | 1 33 00 | 1 35 08 | 1 37 30 | | 1884 | 1 27 23 | 1 28 57 | 1 30 41 | 1 32 37 | 1 34 45 | 1 37 05 | | 1885 | 1 27 01 | 1 28 351/2 | 1 30 19 | 1 32 14 | 1 34 22 | 1 36 41 | | 1886 | 1 26 39 | 1 28 13 | 1 29 56 | 1 31 51 | 1 33 57 | 1 36 17 | |______|_________|__________|_________|_________|_________|_________| | | | | | | | | | Year | 38 deg. | 40 deg. | 42 deg. | 44 deg. | 46 deg. | 48 deg. | |______|_________|__________|_________|_________|_________|_________| | | | | | | | | | | deg. ‘ ” | deg. ‘ ” | deg. ‘ ” | deg. ‘ ” | deg. ‘ ” | deg. ‘ ” | | 1882 | 1 40 29 | 1 43 21 | 1 46 33 | 1 50 05 | 1 53 59 | 1 58 20 | | 1883 | 1 40 07 | 1 42 58 | 1 46 08 | 1 49 39 | 1 53 34 | 1 57 53 | | 1884 | 1 39 40 | 1 42 31 | 1 45 41 | 1 49 11 | 1 53 05 | 1 57 23 | | 1885 | 1 39 16 | 1 42 07 | 1 45 16 | 1 48 45 | 1 52 37 | 1 56 54 | | 1886 | 1 38 51 | 1 41 41 | 1 44 49 | 1 48 17 | 1 52 09 | 1 56 24 | |______|_________|__________|_________|_________|_________|_________| | | |
| Year | 50 deg. |
|______|_________|
| | |
| | deg. ‘ ” |
| 1882 | 2 03 11 |
| 1883 | 2 02 42 |
| 1884 | 2 02 11 |
| 1885 | 2 01 42 |
| 1886 | 2 01 11 |
|______|_________|
An analysis of this table shows that the azimuth this year (1882) increases with the latitude from 1 deg. 28′ 05″ at 26 deg. north, to 2 deg. 3′ 11″ at 50 deg. north, or 35′ 06″. It also shows that the azimuth of Polaris at any one point of observation decreases slightly from year to year. This is due to the increase in declination, or decrease in the star’s polar distance. At 26 deg. north latitude, this annual decrease in the azimuth is about 22″, while at 50 deg. north, it is about 30″. As the variation in azimuth for each degree of latitude is small, the table is only computed for the even numbered degrees; the intermediate values being readily obtained by interpolation. We see also that an error of a few minutes of latitude will not affect the result in finding the meridian, e.g., the azimuth at 40 deg. north latitude is 1 deg. 43′ 21″, that at 41 deg. would be 1 deg. 44′ 56″, the difference (01′ 35″) being the correction for one degree of latitude between 40 deg. and 41 deg.. Or, in other words, an error of one degree in finding one’s latitude would only introduce an error in the azimuth of one and a half minutes. With ordinary care the probable error of the latitude as determined from the method already described need not exceed a few minutes, making the error in azimuth as laid off on the arc of an ordinary transit graduated to single minutes, practically zero.
REFRACTION TABLE FOR ANY ALTITUDE WITHIN THE LATITUDE OF THE UNITED STATES.
_____________________________________________________ | | | | |
| Apparent | Refraction | Apparent | Refraction | | Altitude. | _minus_. | Altitude. | _minus_. | |___________|______________|___________|______________| | | | | |
| 25 deg. | 0 deg. 2′ 4.2″ | 38 deg. | 0 deg. 1′ 14.4″ | | 26 | 1 58.8 | 39 | 1 11.8 |
| 27 | 1 53.8 | 40 | 1 9.3 | | 28 | 1 49.1 | 41 | 1 6.9 |
| 29 | 1 44.7 | 42 | 1 4.6 | | 30 | 1 40.5 | 43 | 1 2.4 |
| 31 | 1 36.6 | 44 | 0 0.3 | | 32 | 1 33.0 | 45 | 0 58.1 |
| 33 | 1 29.5 | 46 | 0 56.1 | | 34 | 1 26.1 | 47 | 0 54.2 |
| 35 | 1 23.0 | 48 | 0 52.3 | | 36 | 1 20.0 | 49 | 0 50.5 |
| 37 | 1 17.1 | 50 | 0 48.8 | |___________|______________|___________|______________|
APPLICATIONS.
In practice to find the true meridian, two observations must be made at intervals of six hours, or they may be made upon different nights. The first is for latitude, the second for azimuth at elongation.
To make either, the surveyor should provide himself with a good transit with vertical arc, a bull’s eye, or hand lantern, plumb bobs, stakes, etc.[1] Having “set up” over the point through which it is proposed to establish the meridian, at a time when the line joining Polaris and Alioth is nearly vertical, level the telescope by means of the attached level, which should be in adjustment, set the vernier of the vertical arc at zero, and take the reading. If the pole star is about making its _upper_ transit, it will rise gradually until reaching the meridian as it moves westward, and then as gradually descend. When near the highest part of its orbit point the telescope at the star, having an assistant to hold the “bull’s eye” so as to reflect enough light down the tube from the object end to illumine the cross wires but not to obscure the star, or better, use a perforated silvered reflector, clamp the tube in this position, and as the star continues to rise keep the _horizontal_ wire upon it by means of the tangent screw until it “rides” along this wire and finally begins to fall below it. Take the reading of the vertical arc and the result will be the observed altitude.
[Footnote 1: A sextant and artificial horizon may be used to find the _altitude_ of a star. In this case the observed angle must be divided by 2.]
ANOTHER METHOD.
It is a little more accurate to find the altitude by taking the complement of the observed zenith distance, if the vertical arc has sufficient range. This is done by pointing first to Polaris when at its highest (or lowest) point, reading the vertical arc, turning the horizontal limb half way around, and the telescope over to get another reading on the star, when the difference of the two readings will be the _double_ zenith distance, and _half_ of this subtracted from 90 deg. will be the required altitude. The less the time intervening between these two pointings, the more accurate the result will be.
Having now found the altitude, correct it for refraction by subtracting from it the amount opposite the observed altitude, as given in the refraction table, and the result will be the latitude. The observer must now wait about six hours until the star is at its western elongation, or may postpone further operations for some subsequent night. In the meantime he will take from the azimuth table the amount given for his date and latitude, now determined, and if his observation is to be made on the western elongation, he may turn it off on his instrument, so that when moved to zero, _after_ the observation, the telescope will be brought into the meridian or turned to the right, and a stake set by means of a lantern or plummet lamp.
[Illustration]
It is, of course, unnecessary to make this correction at the time of observation, for the angle between any terrestrial object and the star may be read and the correction for the azimuth of the star applied at the surveyor’s convenience. It is always well to check the accuracy of the work by an observation upon the other elongation before putting in permanent meridian marks, and care should be taken that they are not placed near any local attractions. The meridian having been established, the magnetic variation or declination may readily be found by setting an instrument on the meridian and noting its bearing as given by the needle. If, for example, it should be north 5 deg. _east_, the variation is west, because the north end of the needle is _west_ of the meridian, and _vice versa_.
_Local time_ may also be readily found by observing the instant when the sun’s center[1] crosses the line, and correcting it for the equation of time as given above–the result is the true or mean solar time. This, compared with the clock, will show the error of the latter, and by taking the difference between the local lime of this and any other place, the difference of longitude is determined in hours, which can readily be reduced to degrees by multiplying by fifteen, as 1 h. = 15 deg..
[Footnote 1: To obtain this time by observation, note the instant of first contact of the sun’s limb, and also of last contact of same, and take the mean.]
APPROXIMATE EQUATION OF TIME.
_______________________
| | |
| Date. | Minutes. |
|__________|____________|
| | |
| Jan. 1 | 4 |
| 3 | 5 |
| 5 | 6 |
| 7 | 7 |
| 9 | 8 |
| 12 | 9 |
| 15 | 10 |
| 18 | 11 |
| 21 | 12 |
| 25 | 13 |
| 31 | 14 |
| Feb. 10 | 15 |
| 21 | 14 | Clock
| 27 | 13 | faster
| M’ch 4 | 12 | than
| 8 | 11 | sun.
| 12 | 10 |
| 15 | 9 |
| 19 | 8 |
| 22 | 7 |
| 25 | 6 |
| 28 | 5 |
| April 1 | 4 |
| 4 | 3 |
| 7 | 2 |
| 11 | 1 |
| 15 | 0 |
| |————|
| 19 | 1 |
| 24 | 2 |
| 30 | 3 |
| May 13 | 4 | Clock
| 29 | 3 | slower.
| June 5 | 2 |
| 10 | 1 |
| 15 | 0 |
| |————|
| 20 | 1 |
| 25 | 2 |
| 29 | 3 |
| July 5 | 4 |
| 11 | 5 |
| 28 | 6 | Clock
| Aug. 9 | 5 | faster.
| 15 | 4 |
| 20 | 3 |
| 24 | 2 |
| 28 | 1 |
| 31 | 0 |
| |————|
| Sept. 3 | 1 |
| 6 | 2 |
| 9 | 3 |
| 12 | 4 |
| 15 | 5 |
| 18 | 6 |
| 21 | 7 |
| 24 | 8 |
| 27 | 9 |
| 30 | 10 |
| Oct. 3 | 11 |
| 6 | 12 |
| 10 | 13 |
| 14 | 14 |
| 19 | 15 |
| 27 | 16 | Clock
| Nov. 15 | 15 | slower.
| 20 | 14 |
| 24 | 13 |
| 27 | 12 |
| 30 | 11 |
| Dec. 2 | 10 |
| 5 | 9 |
| 7 | 8 |
| 9 | 7 |
| 11 | 6 |
| 13 | 5 |
| 16 | 4 |
| 18 | 3 |
| 20 | 2 |
| 22 | 1 |
| 24 | 0 |
| |————|
| 26 | 1 |
| 28 | 2 | Clock
| 30 | 3 | faster.
|__________|____________|
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THE OCELLATED PHEASANT.
The collections of the Museum of Natural History of Paris have just been enriched with a magnificent, perfectly adult specimen of a species of bird that all the scientific establishments had put down among their desiderata, and which, for twenty years past, has excited the curiosity of naturalists. This species, in fact, was known only by a few caudal feathers, of which even the origin was unknown, and which figured in the galleries of the Jardin des Plantes under the name of _Argus ocellatus_. This name was given by J. Verreaux, who was then assistant naturalist at the museum. It was inscribed by Prince Ch. L. Bonaparte, in his Tableaux Paralleliques de l’Ordre des Gallinaces, as _Argus giganteus_, and a few years later it was reproduced by Slater in his Catalogue of the Phasianidae, and by Gray is his List of the Gallinaceae. But it was not till 1871 and 1872 that Elliot, in the Annals and Magazine of Natural History, and in a splendid monograph of the Phasianidae, pointed out the peculiarities that were presented by the feathers preserved at the Museum of Paris, and published a figure of them of the natural size.
The discovery of an individual whose state of preservation leaves nothing to be desired now comes to demonstrate the correctness of Verreaux’s, Bonaparte’s, and Elliot’s suppositions. This bird, whose tail is furnished with feathers absolutely identical with those that the museum possessed, is not a peacock, as some have asserted, nor an ordinary Argus of Malacca, nor an argus of the race that Elliot named _Argus grayi_, and which inhabits Borneo, but the type of a new genus of the family Phasianidae. This Gallinacean, in fact, which Mr. Maingonnat has given up to the Museum of Natural History, has not, like the common Argus of Borneo, excessively elongated secondaries; and its tail is not formed of normal rectrices, from the middle of which spring two very long feathers, a little curved and arranged like a roof; but it consists of twelve wide plane feathers, regularly tapering, and ornamented with ocellated spots, arranged along the shaft. Its head is not bare, but is adorned behind with a tuft of thread-like feathers; and, finally, its system of coloration and the proportions of the different parts of its body are not the same as in the common argus of Borneo. There is reason, then, for placing the bird, under the name of _Rheinardius ocellatus_, in the family Phasianidae, after the genus _Argus_ which it connects, after a manner, with the pheasants properly so-called. The specific name _ocellatus_ has belonged to it since 1871, and must be substituted for that of _Rheinardi_.
The bird measures more than two meters in length, three-fourths of which belong to the tail. The head, which is relatively small, appears to be larger than it really is, owing to the development of the piliform tuft on the occiput, this being capable of erection so as to form a crest 0.05 to 0.06 of a meter in height. The feathers of this crest are brown and white. The back and sides of the head are covered with downy feathers of a silky brown and silvery gray, and the front of the neck with piliform feathers of a ruddy brown. The upper part of the body is of a blackish tint and the under part of a reddish brown, the whole dotted with small white or _cafe-au-lait_ spots. Analogous spots are found on the wings and tail, but on the secondaries these become elongated, and tear-like in form. On the remiges the markings are quite regularly hexagonal in shape; and on the upper coverts of the tail and on the rectrices they are accompanied with numerous ferruginous blotches, some of which are irregularly scattered over the whole surface of the vane, while others, marked in the center with a blackish spot, are disposed in series along the shaft and resemble ocelli. This similitude of marking between the rectrices and subcaudals renders the distinction between these two kinds of feathers less sharp than in many other Gallinaceans, and the more so in that two median rectrices are considerably elongated and assume exactly the aspect of tail feathers.
[Illustration: THE OCELLATED PHEASANT (_Rheinardius ocellatus_).]
The true rectrices are twelve in number. They are all absolutely plane, all spread out horizontally, and they go on increasing in length from the exterior to the middle. They are quite wide at the point of insertion, increase in diameter at the middle, and afterward taper to a sharp point. Altogether they form a tail of extraordinary length and width which the bird holds slightly elevated, so as to cause it to describe a graceful curve, and the point of which touches the soil. The beak, whose upper mandible is less arched than that of the pheasants, exactly resembles that of the arguses. It is slightly inflated at the base, above the nostrils, and these latter are of an elongated-oval form. In the bird that I have before me the beak, as well as the feet and legs, is of a dark rose-color. The legs are quite long and are destitute of spurs. They terminate in front in three quite delicate toes, connected at the base by membranes, and behind in a thumb that is inserted so high that it scarcely touches the ground in walking. This magnificent bird was captured in a portion of Tonkin as yet unexplored by Europeans, in a locality named Buih-Dinh, 400 kilometers to the south of Hue.–_La Nature_.
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THE MAIDENHAIR TREE.
The Maidenhair tree–Gingkgo biloba–of which we give an illustration, is not only one of our most ornamental deciduous trees, but one of the most interesting. Few persons would at first sight take it to be a Conifer, more especially as it is destitute of resin; nevertheless, to that group it belongs, being closely allied to the Yew, but distinguishable by its long-stalked, fan-shaped leaves, with numerous radiating veins, as in an Adiantum. These leaves, like those of the larch but unlike most Conifers, are deciduous, turning of a pale yellow color before they fall. The tree is found in Japan and in China, but generally in the neighborhood of temples or other buildings, and is, we believe, unknown in a truly wild state. As in the case of several other trees planted in like situations, such as Cupressus funebris, Abies fortunei, A. kaempferi, Cryptomeria japonica, Sciadopitys verticillata, it is probable that the trees have been introduced from Thibet, or other unexplored districts, into China and Japan. Though now a solitary representative of its genus, the Gingkgo was well represented in the coal period, and also existed through the secondary and tertiary epochs, Professor Heer having identified kindred specimens belonging to sixty species and eight genera in fossil remains generally distributed through the northern hemisphere. Whatever inference we may draw, it is at least certain that the tree was well represented in former times, if now it be the last of its race. It was first known to Kaempfer in 1690, and described by him in 1712, and was introduced into this country in the middle of the eighteenth century. Loudon relates a curious tale as to the manner in which a French amateur became possessed of it. The Frenchman, it appears, came to England, and paid a visit to an English nurseryman, who was the possessor of five plants, raised from Japanese seeds. The hospitable Englishman entertained the Frenchman only too