Popular Science Monthly/Volume 14/January 1879/Popular Miscellany

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What Medicine owes to Galileo.—In a lecture on the history of instruments of precision in medicine, a synopsis of which is published in the Medical Record, Dr. S. Weir Mitchell gives to Galileo Galilei the credit of having contrived the first instrument of this kind, viz., the pulsilogon. Desiring to apply some test of the regularity of the swing of the lamp-pendulum in the Pisa cathedral, he is said to have used that most wonderful of clocks, the pulse, for that purpose. This was a grave moment in the history of medicine—"the birth of precision," says Dr. Mitchell. From this use of the pulse as a test of the regularity of the pendulum he was led to use the pendulum as a measure of pulse-rate—thus making the pendulum a pulsilogon. The method of using it was most ingenious. Having always a pendulum of equal weight, he set it swinging, and then shortened or lengthened the string until the beats corresponded with those of the patient's pulse. Then he measured the length of the string, and one person's pulse would be represented arbitrarily but most precisely by say ten inches, another's by eight inches, and so on. Galileo seems to have given little thought to the perfection of this instrument, and does not speak in any of his essays of the medical use of the pendulum. Many years later Sanctorius described an instrument for measuring the pulse which was in no respect different from that of Galileo, and which was called by the same name—pulsilogon.

Plant-Respiration.—From experiments made by Mr. J. Jamieson, and published in Nature, it would appear that fresh sections of many fruits and other vegetable structures, as potato, give the. characteristic reactions of ozone, viz., causing separation of iodine from iodide of potassium, and turning tincture of guaiacum blue, the intensity of the reactions depending mainly on the comparative freshness of the fruits and vegetables. Mr. Jamieson further finds that these structures contain a substance which acts as an ozone-carrier, or Ozonträger, to use Schönbein's expression, a substance which transfers ozone from hydrogen-peroxide, and similar bodies. This is shown by the fact that, if the guaiacum is not blued at all, or only slightly, the blue color becomes very marked when a drop of ethereal solution of hydrogen-peroxide is added. From these observations the author infers—1. That the oxygen inhaled by living plants, and even by pulled fruits, for a time is ozonized, probably by entering into loose combination, as is the case with oxygen in the blood of animals; and, 2. That it is probable that the ozone-transferring substance existing in almost every fresh vegetable structure is that with which it is loosely combined, as the oxygen in the blood is with the hæmoglobin of the red corpuscles. This element in plants is gradually destroyed as decay comes on, and ceases to perform its ozone-transferring function when the fruit, etc., containing it is cooked. It is not chlorophyl, as is shown by its situation, and it seems to be intimately associated with the vascular tissue. From analogy with the animal substances, hæmoglobin, fibrin, myosin, etc., which have a similar action, it may be presumed to be proteinaceous, though the author is unable more exactly to indicate its chemical and other characters.

Growth of Mining Engineering In the United States.—Thirty years ago the profession of the mining engineer was almost unknown in the United States; to-day the American Institute of Mining Engineers numbers over 700 members. The state of things which existed thirty years ago. will be understood from the following passage, which we take from Mr. E. B. Coxe's presidential address to the members of the Institute at its last meeting: "Of the few we then had worthy of the name of 'mining engineer,' some studied in the Continental academies, and others were graduates in the school of practical experience, and had learned their profession in mines and smelting-works. Their work consisted principally in making surveys and maps of mines and mining properties, geological reports, and analyses of ores; but the mining engineer, whom we often meet with now, who has studied chemistry, physics, mineralogy, geology, mechanics, and drawing; who is more or less familiar with machinery and its construction, and with the practical management of mines or smelting-works, and who is an expert in some one branch of his profession—would have been very difficult if not impossible to find in the United States. The inducements held out to ambitious and talented young men to enter the profession were, it must be admitted, very small. By a large portion of the community, a mining engineer was considered to be merely a bait with which unsophisticated capitalists were to be caught, and his opinions were considered to be worth so much a page, and to favor any view which his employer wished to have advocated. He was seldom consulted as to the proper method of working a mine or running a furnace; he was rarely called upon by directors of works, except for extraordinary work, such as to give the direction in which a tunnel should be driven, or to analyze a new ore or limestone. There was no recognized standard in the profession, and there were great openings for unprincipled adventurers, of which many charlatans took advantage. Up to within fifteen years, mining engineers were too often regarded by those who had dealings with them with great distrust, and well-educated persons may yet be found who have no idea what a mining engineer is, nor what he is called upon to undertake. This feeling is, however, wearing away. We now have mining engineers whose names are as well known abroad as at home; whose opinions are respected and paid for, although, I am proud to say, they cannot be bought. We have schools whose graduates are well qualified to enter the ranks of the profession when they have obtained the proper practical experience; and there are few parts of the country without mining engineers of established reputation, unless, in consequence of the peculiar condition of the locality, there is no need of their services."

Studies of a Mummy.—Mr. Frank Buckland, having received from a friend who had been visiting Egypt a mummy-head, set about examining the curiosity, with what results he informs us through the columns of Land and Water. From the general contour of the head he infers that it is that of a woman. The actual features cannot be seen, being covered with a sort of mask of linen cloth. Underneath this can be discerned the outlines of the face; the pupils of the eyes are marked with a black spot. The mummy wears a wig! Mr. Buckland found the whole head covered with what at first appeared to be rolls of hair, but which turned out to be an imitation of hair. The rows forming this wig are arrayed in three tiers, overlapping each other. The lowest tier begins from the top of the ear, and runs almost straight across the forehead; it is not unlike the fashion of hair worn by some ladies of the present day. "To try the effect," adds Mr. Buckland, "I put a modern, smartly-trimmed hat on the head of this Egyptian lady. I see that the fringe of hair is the same as the fringe of the present time. On the whole, there is a little more chic about it." Having washed one side of the mummy's face with warm water and a sponge, and again put on a modern hat, he was more convinced than ever that the head is that of a lady—"very good-natured and smiling."

Effects of English Rule in India.—Mr. C. Macnamara, surgeon to the Westminster Hospital, London, was for twenty years engaged in practice in India, and during that time had every opportunity of learning the feelings and opinions of the natives regarding the present state of things in that country. According to Mr. Macnamara, the deep and growing conviction of many of them is that, although England has in India preserved many millions of human beings from the calamities of anarchy and chronic warfare, nevertheless native society is becoming rapidly disorganized. A vast number of the old families have disappeared; the mothers and wives of the rising generation see their educated sons and husbands given over to vices formerly never heard of, utterly heedless of family or any other ties, and they contrast all this with times past, when there was not so much law, education, or taxation, but when the greatest stain that could be cast on a man's name was that of being an undutiful son. In Mr. Macnamara's opinion all this results from "purely secular education." The rising generation of educated Hindoos break away from the native religion, entirely ignore the existence of a God, and live absolutely for self. "The outcome of a purely secular education," writes Mr. Macnamara, "is gross materialism and rank socialism. Hence the necessity of suppressing the vernacular press, a measure calculated, it may be, to smother for a period one of the many outlets by means of which Europeans had an opportunity of ascertaining the state of feeling among the natives of the country, and which [sic] I fear will too certainly burst forth in an insurrection in comparison with which the mutiny was a mere brawl."

Our Parks.—In a recent paper on "Our Parks," read before the New York Academy of Sciences, Dr. E. Seguin vigorously protests against the policy that is rapidly surrendering the Battery to commercial uses, and destroying its value for esthetic and health-giving purposes. The beautiful view of the harbor which the Battery once afforded is gradually being narrowed: to the west by Castle Garden, formerly a simple terrace—a lookout, now an immigrant shed; toward the east six buildings form an immense barrier, behind which none would suspect how near the ocean displayed its ever-changing scenes; from the sea the city looks as if inclosed by barracks, from the land it is the sea that appears to be imprisoned. The little space for an outlook remaining is now threatened with invasion by Government buildings, the city consenting with offers of additional land if required. A total obstruction of the view will follow next, completing the severance of the city from the bay, and presenting the shocking contrast of a harbor unequaled in grandeur leading up to a row of barracks on the water-front—no monuments in view, the ocean-breeze shut out, all perspective destroyed; the whole scene a violence to the eye and an humiliation to patriotic pride.

Preceded by the destruction of St. John's Park, and the attempt of last year to ruin the Washington play-ground, Dr. Seguin regards this as a third plot against the best interests of the city, coolly set to execution for no apparent purpose save the destruction of what is both a health resort and a powerful educating agency for the children and youth of the metropolis; and thus blunting the sense of the beautiful by cutting them off from the enjoyment of the natural scenery of which New York, above all other cities, is the fortunate possessor.

All right thinking people will agree with Dr. Seguin that an exactly opposite policy should be adopted and carried out by the municipal authorities. This whole shore up to its original limits should be thrown open to the bay, and made to present to the stranger the noble face of a great city, the hospitable welcome of a great nation. It should be made an entrance of honor for distinguished guests, where the greetings of a cultured people could not be drowned by the rush and turmoil of trade. It should be rescued from its present and prospective degradation, and, by a wise combination of Nature with art, converted into a school for the millions that in future generations would make it a resort. To this end says Dr. Seguin: "The waves of the bay should be made to expire in marble basins, fronting the widened entrance to Broadway, perceptible through the trees. Where the land and water meet the vegetation, transformed from terrestrial to aquatic, may extend from the shore to the reefs beyond, and here also could be established subterranean aquaria, whose population might be made more varied and rich in the life of the sea than that which now delights and instructs the visitors at Brighton." Dr. Seguin gave several interesting illustrations of the great influence exerted by early impressions in shaping the future of the individual, and contended that every opportunity should be seized to make such impressions contribute to elevation of character, and to the encouragement of noble aims. He also called attention to the advantages that would follow the union of outdoor with indoor teaching by what he terms the mobilization of the schools.

The Light of the Sun's Corona.—Before the occurrence of the solar eclipse of 1878, Mr. W. T. Sampson, U. S. N., made elaborate preparations for studying minutely the corona's spectrum, with the sole view of deciding, by the absence or the presence in it of dark lines, whether the light is reflected sunlight, whether it is due to the self-luminous matter of the corona, or whether it is due to both of these causes combined. In the American Journal of Science he describes the instruments used for this research, and the manner in which they were employed. His conclusion is that, inasmuch as he failed to see in the corona spectrum the dark lines of the sun's spectrum, therefore the light of the corona is not all reflected light. The considerations which confirm him in this conclusion he states as follows: "Until this eclipse no observer has ever seen the dark lines in the spectrum of the corona except M. Janssen, who reported dark lines, notably D in 1871, but much more difficult to see than the bright lines. Several observers during the recent eclipse failed to see the dark lines, though they looked for them carefully. While I do not question the results of observers who report the presence of dark lines, I think all the observations taken together show that the continuous spectrum of the corona is not the spectrum of the sun. Aside from this, Prof. Arthur W. Wright made measurements of the polarization of the light of the corona, the first time, I think, it has been attempted, and has found the polarization to be but a small percentage of the whole light emitted. Although all reflected light does not reach us as polarized light, yet I think the small percentage of polarization, taken with the faintness of the dark lines, indicates that the corona is, to a considerable extent, self-luminous. The meteoric dust not only reflects the sun's light, but it is continually showering upon the sun, and in its passage through the atmosphere is rendered incandescent."

Investigating the Cotton-Worm.—Prof A. R. Grote is at present visiting the cotton growing States for the purpose of studying there the habits of the cotton-worm, and more particularly of determining whether the fly from which it comes is acclimated in those States, or whether it is annually imported. The latter opinion, as our readers are aware, is the one held by Prof. Grote, and it appears to be confirmed by this later investigation. According to his theory, the fly comes from the West Indies with the south winds every year. Having reached our cotton-producing States it there raises its first brood. The eggs are deposited on the under side of the cotton-plant leaf. In about three weeks the young worm "webs up" and becomes a black chrysalis in a thin cotton-cocoon within a fold of the leaf, and in due time the perfect insect emerges. This new fly, born in the South, moves in a general northerly direction, and in this way the country is overrun by the several ensuing broods. If the worm appears while yet the plant is young, the planter can exterminate it by the use of poison; but if it comes late it will not do harm enough to warrant much expense in killing it. Paris-green in a liquid form, or dilute carbolic acid, kills the worm when applied to the under side of the leaf as spray. Care must be taken to keep these poisons from the seed-cotton, and they should only be employed against the first brood of worms before the bolls open.

An Eastern Fish-Story.—A series of interesting letters is now appearing in Land and Water, entitled "Recollections of Bangkok," and in one of them a good description is given of the mode of capturing insect prey, followed by a species of "archer fishes," several specimens of which are kept in a small pond in the grounds attached to the palace of the "Second King" of Siam. It is much to be regretted that the author neither describes these fishes nor notes any particulars by which the species might be determined. Our readers will find in the Monthly for January, 1878, an illustrated paper on "Archer-Fishes." When the writer in Land and Water came to the pond its finny inhabitants were found to be in a high state of excitement, the cause of which was soon evident. "A small branch covered with black ants had been picked by one of the attendants off one of the overhanging trees; and, holding this a few feet over the pond, volleys of minute globules of water were directed at it from the mouths of all the little fishes crowded underneath. This was continued until all the ants were knocked off into the water. Then ensued a scramble for the prey. Any small insect within their range met the same fate, and they shot with the most unerring aim. As I stood watching the curious sight, close to the edge of the pond, a small fly lighted on my hand, but was hardly seated before a volley of watery bullets knocked him off his perch, though at a range of four or five feet. These little fishes are, I believe, only known in some parts of Siam and Burmah; they are small, not more than six or seven inches, and in shape like a smelt. I am not aware that I have ever seen any description of them."

"Are the Elements elementary?"—Mr. Norman Lockyer has realized the alchemist's dream, the transmutation of metals. In the presence of a small party of scientific men, Mr. Lockyer, by the aid of a powerful voltaic current, volatilized copper within a glass tube, dissolved the deposit formed within the tube in hydrochloric acid, and then showed, by means of the spectroscope, that the solution contained no longer copper, but another metal, calcium, the base of ordinary lime. The experiment was repeated with other metals and with corresponding results. Nickel was thus changed into cobalt, and calcium into strontium. All these bodies, as is well known, have ever been regarded as elementary—that is, as incapable of being resolved into any components, or of being changed one into another. It is on this basis that all modern chemistry is founded, and, should Mr. Lockyer's discovery bear the test of further trial, our entire system of chemistry will require revision. The future possibilities of the discovery it is difficult to limit. The great object of the old alchemists was, of course, to transmute base metals into gold, and so far as our knowledge goes there is no reason why copper should not be changed into gold as well as into calcium. The means at present employed are obviously such as to render the process far more costly than any possible results can be worth; but this is necessarily the case with most scientific discoveries before they are turned into commercial facts. Mr. Lockyer is one of our best living spectroscopists, and no man with a reputation such as his would risk the publication of so startling a fact as he has just announced to the scientific world without the very surest grounds. He is known by his friends as somewhat sanguine, and he does not pretend to be an accomplished chemist, but he was supported yesterday by some of our leading chemists, all of whom admitted that the results of his experiments were inexplicable on any other grounds but those admitting of the change of one element into another, unless indeed our whole system of spectrum analysis is to be upset, the other horn of a very awkward dilemma. Since a hundred years ago Priestley discovered oxygen and founded modern chemistry there has been—there could be—no discovery made which would have such an effect on modern science as that the so-called elements were no longer to be considered elementary.—London Daily News.