Popular Science Monthly/Volume 48/December 1895/Fragments of Science

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Fragments of Science.

Constituents of Ocean Bottoms.—In his summary of the results of the Challenger Expedition, Dr. Murray classifies marine deposits as littoral, shallow water, and deep sea. Such deposits are, in origin, either land-derived or pelagic—that is, of the ocean. The land-derived deposits edge the shores, for the finest river mud is rarely met with as far as three hundred miles from the coast, and particles so large as to be called sand remain close to it. Regarded in this light, the whole ocean beyond the three-hundred-mile belt of "territorial waters" possesses a distinct individuality, invaded by no material of land origin except the mud and boulders carried by drifting ice, the dust which settles out of the air, and scraps of floating pumice from volcanic eruptions. In a few patches less than seventeen hundred fathoms deep, far from land, the remains of relatively large and delicate shells which lived on the surface abound at the bottom, mixed with innumerable shells of dense, nearly microscopic foraminifera and a little clayey matter, the whole receiving the general name of pteropod ooze, from the characteristic shells of pteropods which occur in it. In deeper waters no pteropod or other delicate shells are found, and the calcareous meal of foraminifera, closely resembling softened chalk, is called globigeiina ooze, from the particular genus of surface-living organism which occurs in largest proportion. At greater depths globigerina ooze is found in which the microscopic shells appear much corroded; and finally, in the deeps or areas more than three thousand fathoms below the surface, the deposit is almost free from carbonate of lime, and forms a stiff red clay composed of decomposed volcanic or atmospheric dust and those constituents of shells that are not readily dissolved by sea water. The process of formation has been clearly shown. Over the whole surface the same shell-bearing creatures die in myriads; their bodies fall continuously as a gentle calcareous snow shower through the water, which slowly dissolves them. The large thin shells vanish first, and only reach the bottom in shallow water; the dense spheres of the pinhead and smaller foraminifera resist longest, and only the insoluble residue reaches the greatest depth. Thus the excess of carbonate of lime dissolved in the deepest layers of the ocean is readily explained. The red clay forms so slowly that particles of metallic dust from exploded meteorites, which are covered up by the surface accumulations everywhere else, form an appreciable proportion of its substance. In places where silicious organisms like sponges and radiolarias are numerous on the surface, their glassy spicules form a considerable ingredient in the red clay, which, when the proportion reaches a considerable value, is called radiolarian ooze. Again, in the cool and less saline water of the southern ocean, and in other cases where the water is freshened, the microscopic, silica-sheathed, self-moving plants known as diatoms swarm in such vast numbers that the deposit consists in very large degree of their shells. When the proportion reaches one half it is described as diatom ooze. The red clay covers about fifty-one million square miles of the ocean floor; globigerina ooze is spread over about fifty million square miles; and diatomooze occupies a belt encircling the globe in the southern ocean, with a total area of about ten million square miles. These three kinds of deposits are thus believed to spread over a surface twice as extensive as all the land of the earth. The terrigenous or land-derived deposits occupy about nineteen million square miles, and one of the strongest arguments for the existence of an antarctic continent is the fact that they border the belt of diatom ooze on the southward wherever it has been passed.

Tenacity of Old Rituals.—While exploring an ancient cemetery near Cuzco, Peru, Mr. George A. Dorsey observed a curious ceremony performed by the Quichua Indians which illustrated to him the tenacity with which the old rites are held, and the manner in which recognition of living spirits of the dead and sacrifice to them still prevail. The men had been unwilling to assist him in disturbing the tombs of the dead, because they contained the remains of their ancestors, to remove which would be sacrilege, but were drafted into his service by a peremptory order from the prefect. On approaching the tombs the men knelt and pronounced in unison an invocation which began with a recital to the spirits of the chiefs as sons of the great Pachacamac of the doctrine of the Trinity and continued with the address: "Chiefs, sons of the sun, we have not come to disturb your tranquil sleep in this your abode. We have come because we have been compelled by our superiors; toward them may you direct your vengeance and your curses!" Then they made offerings of coca, aguardiente, and chicha, and called on a lofty, snow-capped mountain, Sancahuara, to witness the truth of their invocation.

A New Bear.—A new bear is mentioned by William H. Dall, in Science, as having been observed frequenting the vicinity of the glaciers of the St. Elias Alpine region. It is regarded by the Indians and hunters as distinct from both the black and the brown bears of Alaska. It is not large, no skin being more than six feet long, is shy, and not so fierce as the other bears. Its general color resembles that of the silver fox. The fur is not very long, but is remarkably soft; and it has a rich bluish-black under fur, while the longer hairs are often white, at least in the distal half. The dorsal line, the back of the ears, and the outer faces of the limbs are jet-black. The sides, neck, and rump are black and silver. The under surface of the belly and the sinuses behind the limbs are grayish white or pure white. The bright tan color of the sides of the muzzle and the lower fore part of the cheeks is invariable, and has not been seen by Mr. Dall in any other American bear. The structure of the claws is adapted to the climbing of trees. Mr. Dall believes that it is at least a well-defined local race, and proposes for it the racial name of Emmonsii. The Sitka fur dealers call it the glacial or blue bear. The Indians speak of another animal, unknown to naturalists, as inhabiting the higher mountains of the mainland. It is described as resembling the mountain goat, with horns nearly as long, but almost straight.

Agriculture on City Lots.—A satisfactory report upon the working of the experiment tried in Detroit in 1894, of engaging the poor and unemployed of the city in the cultivation of vacant lands and lots, is published by the Sterling Publishing Company, New York. About four hundred and fifty acres, or seven thousand city lots, were divided into quarter-and half-acre tracts, and about three times as many applications for allotments were received as could be granted. The crops were planted, cultivated, and harvested by the people themselves, under the supervision of the committee; about nine tenths of the pieces were well taken. care of. The committee estimate that the potato crop averaged about fifteen bushels per lot, giving fourteen thousand one hundred and seventy-five bushels in all; and large quantities of beans, turnips, and other vegetables were raised and daily consumed, of which no record was made. The estimated value of the crops produced was from twelve to fourteen thousand dollars, to say nothing of the potatoes that were eaten before they had attained any considerable size. The entire cost to the committee was thirty-six hundred dollars, a sum that was made up by subscriptions. "Should the experiment be continued, it is best to get tracts of as many in a piece as possible, and, if poor land, to collect the sweepings of the streets to be put upon the land in the spring or carry it upon the land from time to time as collected to enrich the soil. . . It is believed that with the experience gained this year, the plan could in many respects be improved and the cost greatly reduced by beginning it in time. The committee finds that about one third of an acre is sufficient land for a family to raise enough potatoes to last them through the winter and furnish vegetables through the summer." It should be recollected that the experiment was tried under many disadvantages. It was a step in the dark; vacant city lots are in appearance the most unproductive soil imaginable; the planting was not begun till late in June, and the season was one of the worst for garden crops which the country had had for many years. Yet the success was great. A like success is claimed for a similar experiment tried in Buffalo, N. Y., in 1896. Many problems of economy, morals, and good taste would be solved if the system should become general and permanent.

Onyx Marble.—The stone called onyx marble, which is much used now in ornamental articles of furniture, is really a calcareous or lime rock, which has been deposited as a travertine or tufa from water in which it was held in solution. Water, while it can not alone dissolve lime rock, can take up considerable quantities of it when it holds carbonic acid in solution, but must drop it again when the carbonic acid has escaped. Both these processes are of common occurrence, and hence, in the springs where they are going on, tufas or travertines are formed. We know this much of what takes place, but we do not know, says Mr. George P. Merrill, in his paper on this subject, just what are the conditions governing the compactness and condition of crystallization of the deposit—why in some cases it should be susceptible of an enamel-like polish, and in others should be light and tufaceous. Onyx marble is also found in caves as a constituent of the stalagmites and stalactites which grow there, and much in the same way as in the springs. Water charged with carbonic acid percolating through the roof of the cave brings down dissolved limestone, hangs in drops to the roof, is evaporated or loses its carbonic acid, and leaves a calcareous deposit to be enlarged by continuous accretions. It rarely happens that all the water evaporates from the ceiling of the cave. Some of it usually falls to the floor, whence it is in its turn evaporated and leaves there a continually growing deposit—a stalagmite. As the water in percolating through the roof dissolved only the pure lime carbonate, or took up only a trace of impurity, these stalactitic and stalagmitic deposits are of purer lime, refined and recrystallized under new conditions. It follows almost from necessity from their mode of origin that the beds of onyx marbles, both spring and cave deposits, are as a rule far less extensive and regular in their arrangement than are the ordinary stratified and imbedded marbles. Spring action is more or less intermittent, and the place of discharge, as well as the character of the deposit, is variable. The deposit usually takes the form of a comparatively thin crust, conforming to the contours of the surfaces on which it lies. The various layers thicken and thin out irregularly, and are often lenticular in cross-section. Sound and homogeneous layers of more than twenty inches in thickness are not common. A marked and beautiful feature of the onyx marbles in general, and particularly of those which originate as spring deposits, is the fine, undulating parallel bands of growth or lines of accretion shown on a cross-section, which are due to its mode of origin through successive depositions upon the surface. The stone owes its chief value for decorative purposes to its translucency, fine venation, and color. Sometimes the original hues have become enhanced by oxidation and through the development of reticulating veins of small size, into which percolating waters have introduced new coloring substances or locally oxidized the protoxide carbonates which seem to form the chief colouring constituent. The finer grades of stone of this type are obtained from few and scattered localities, and, except those that are of cave origin, generally, so far as the author has observed, the most eminently desirable for ornamental purposes are from hot and arid countries and regions not far distant from recent volcanic activity.

Giant Mountain Plants.—Two Swiss botanists, MM. Sommier and Sevier, who have recently explored the Caucasus, tell of the discovery of a mountain flora of giant herbaceous plants, of which little was known before, and which they designate as macro-flora. At the altitude of about fifty-eight hundred feet some plants reach a size which they never attain in the valleys. A campanula, which does not exceed about two feet below, grows to about six feet at that height, with an unpliable stem. The large, kidney-shaped leaves of a valerian are borne at the end of petioles so rigid that they can be carried as parasols. These fields resemble the pampas, and the rocks are hidden in a growth of large plants of different kinds. The luxuriance of this vegetation is ascribed by the authors partly to the extraordinary fertility of the soil, from which the accumulated mold of ages has never been removed; while, as a second way of accounting for them, they are regarded as survivals of the grand flora of some former geological age.

A New Race of Ancient Egyptians.—The continued explorations of Mr. W. Flinders Petrie on the west side of the Nile below Thebes have resulted in the discovery of what he regards as a hitherto unknown race of men, who probably lived in Egypt about five thousand years ago. In the near neighborhood of sites yielding potteries of the best known Egyptian dynasties he found the remains of a town, with cemeteries of which about two thousand graves were excavated, in which there was not a single Egyptian object or the trace of the observance of any Egyptian custom. The bodies, instead of being mummified or buried at full length, were contracted, with heads to the south and faces to the west. They were of fine physiognomy, without prognathism; of remarkable stature—some being more than six feet high and of development of legs indicating a hill race; with brown and wavy but not crisp hair, aquiline nose, and long, pointed head. No hieroglyphics or characters suggesting writing were found, beyond a few scratches on vases. Their vessels were perfect in form—all hand-made—yet their art was of the rudest. A picture in monochrome on one of the vases represents a boat with two cabins, rowed with oars, bearing the ensign of five hills, with ranges of hills on either side, and ostriches striding along. A game of ninepins was found, in which the pieces are formed of stone, with balls of syenite about the size of peas. The people used green paint made from malachite for marking their eyes, and many of the slate palettes on which this was ground were found. Their funeral rites appear to have included a kind of ceremonial cannibalism. They are supposed to have lived about the time from the seventh to the ninth dynasties. In the same region, in a spot exactly resembling the river gravels of England and France, large quantities of similar palæolithic remains were found.

Signs of the Times.—In an article under the above title, by Edward Atkinson, in the August number of the Engineering Magazine, is the following comment on the recent celebration of the opening of the ship canal at Kiel: "There is something rather grotesque in the picture which the nations have made at the opening of the ship canal at Kiel. The object of that canal is mainly to promote commerce, to facilitate exchange, to bring to the occupants of a rather poor soil in middle Europe a necessary supply of food and fibres from other parts of the world, and also a necessary supply of the crude products of the non-machine-using nations for conversion into finished goods for home use and export. In order to celebrate the opening of this peaceful way for commerce, there gathered a collection of naval bulldogs, each for the time muzzled, but in many instances with growl barely suppressed. In a rough-and-ready way one may estimate the cost of this fleet of one hundred great armor-clad ships of war, with twenty-five lesser vessels, at approximately $200,000,000, which is probably four or five times the cost of the peaceful water-way, the opening of which they were called together to celebrate. The United States was represented by one battle ship and, I believe, by one of our two 'commerce-destroyers,' so called. The two armored ships so named cost nearly $7,000,000—a sum nearly equal to the entire endowment of Harvard University—while the annual expense of keeping the two in commission is nearly as great as the pay roll of the same university. The only commerce of any importance upon which these destructive ships of war could exert their force would be that of Great Britain and Germany, our two largest foreign customers for the excess of our farm products, which would rot upon our fields if we could not sell them for export. Any commentary upon these grotesque conditions would perhaps be superfluous. As time goes on this waste of preparation for war will be stopped in more than one way. First, because no ship can carry armor which will defend it from the latest type of guns. Next, because no land force can stand in the face of guns discharging over six hundred shots per minute, warranted to kill at more than a mile. But lastly, as to European states, because the limit of taxation has been reached. New taxes can not be invented and new sources of revenue can not be discovered which will warrant even the maintenance of existing armies and navies."

Two Wild Vegetables of Merit.—T. W. Card, of the experiment station at Lincoln, Nebraska, calls attention, in Garden and Forest, to two wild vegetables which he thinks merit the attention of cultivators.

One of these, which is already gathered from the fields and used to a considerable extent in the West, is the wild lettuce; there are two species common on the plains, Lactuca canadensis and L. Ludoviciana. They are chiefly used for greens, and fill an important place for this purpose, as they come in advance of spinach, and when no other greens are offered in the market. The other plant is the ground plum or buffalo pea of the plains (Astragalus crassicarpus). This is found abundantly in the draws or low grounds of the unbroken prairie. The plant is a perennial, apparently perfectly hardy, and very productive. The fruit resembles gooseberries in size and general appearance. It is borne in numerous clusters, very early in the season. When cooked like string beans the fruit forms a very acceptable dish. The chief point which recommends the plant for cultivation is the time at which the fruits are ready for use, some of them ripening as early as May 7th.

Protecting Iron and Steel against Rust.—Gesner's method, described in La Revue Scientifique, consists in forming on the surface of the metal a double carbide of hydrogen and iron. A bar thus coated can be bent through an angle of forty-five degrees without disturbing the layer. The process is as follows: The surface to be coated is first thoroughly cleaned from rust. A couple of gas retorts are placed alongside each other and raised to a temperature of from 600° to 700° C. The articles to be treated are then placed in these retorts for about twenty minutes, after which a current of hydrogen is passed through the retorts for forty-five minutes. A small quantity of naphtha is then introduced, the supply being maintained for ten minutes. It is then stopped, the current of hydrogen being kept up fifteen minutes longer, when it is stopped and the retorts are allowed to cool to 400° C., and when this temperature is reached the doors can be opened and the finished product removed. The coating thus given has a bluish color.

The Microscope in Metallurgy.—Micrometallography—the examination of samples of iron and steel by looking at etched or polished sections through a microscope—is rapidly taking its place in the routine work of metallurgical laboratories. It has been developed from petrography. Dr. Sorby, an Englishman, who in 1864 submitted some photographs of opaque sections of various kinds of iron and steel to the British Association, seems to have been among the first workers in this field. The process of preparing the specimens is complicated and somewhat tedious, but the results fully repay the worker. By means of these methods steel has been found to contain five main constituents: Pure iron, ferrite; carbide of iron, cementite; sorbite, of uncertain composition; martensite and froostite; the latter marks the transition of soft iron into hardened steel. Sorbite, froostite, and martensite appear to be solidified solutions of various forms of carbon in divers forms of iron, for it seems clear that metallographic work on steel brings into prominence the existence of allotropic forms of iron. An exhaustive monograph on the progress of micro-metallography during the past ten years, by M. F. Osmond, may be found in the Bulletin de la Société d'Encouragement, vol. x, p. 480, 1895.

Audibility of Fog-horn Signals.—Some time ago there appeared a description of some experiments which went to prove that around each siren there is a zone, about one and a half nautical miles broad, within which fog signals can not be heard, although they are distinctly heard outside that zone. These statements have been recently confirmed by a series of experiments which are noted in Nature. In one of these the vessel steamed with the wind straight toward the lightship from a distance of four and a half nautical miles. At a distance of two miles and three quarters the sound became faintly audible, and suddenly increased in loudness at two miles and a half, retaining the same intensity up to two miles distance. From one and three quarters to one and a half mile the note was scarcely audible, but then it immediately increased to such an extent that it appeared to originate in the immediate neighborhood of the vessel. The steamer at this point reversed its course, and the fluctuation over this part of the course was found to be the same, except that it was even more strongly marked. The vessel was again reversed, and at half a mile the sound disappeared entirely, to reappear at a quarter of a mile from the lightship; after which it gradually and steadily increased in intensity until the latter was reached.

The Ideals of Modern Medicine.—We take the following from President Sir T. Russell Reynolds's address before the recent meeting of the British Medical Association in London: "The outcome of what I have been saying is this: that the scattered fragments of knowledge and guesses at truth of many years have been gathered into a focus during the past twenty-five years; that the vegetable life extracting from the mineral world the materials it needs for growth and production of powerful agencies for good in the form of food and medicines, and for evil in the form of poisons, has given itself up to the growth of animal life, with its much more complex organs, and for cure of ills once thought beyond the reach of human aid; but that, thanks to man's scientific ardor and industry, it has again shown itself to be our servant, our helper, and our protector. These are not dreams of the study, they are facts of the laboratory and of daily life; and in using that word 'life' again, I must endeavor to emphasize still more forcibly upon you my urgent belief that it is to living agencies and their employment that we must look for help in the care of infancy, the conduct of education—moral, mental, and physical—the training up of character, as well as of limbs; that it is the guidance of living functions, in the choice of living occupations, be they either of hard work or of amusement. It is to these we must appeal if we would see the mens sana in corpore sano; and then it will be to these that we may confidently look for help, when the inroads of age or of disease are at hand, often to cure us of our trouble; or if not, to give us rest and peace."

City Government.—The corporation of the city of London is one of the most ancient bodies in England, and its record shows a constant succession of capable men and a uniform policy. It was in existence before Parliament, and it has seen the downfall of more than one royal house. The secret of its success has lain in the fact that municipal dignity has always been confided to the hands of men of business, who had shown their capacity to manage private affairs of great magnitude before they were intrusted with those of their neighbors. Their training had been such as to remove them as far from the hide-bound conservatism of the official as from the destructive reforming energy of the professional politician. As an instance of the methods employed may be cited the fact that perfect and exact records, with the exception of three years, of every penny spent on London Bridge since 1831 are in existence and in splendid preservation. These facts, which we take from Engineering, differ so extremely from those brought to light by the recent reform investigations in American cities as to seem worthy of notice,

Pithecanthropus Erectus—At the recent meeting of the zoölogists at Leyden, an interesting discussion occurred over some bone fragments (a femur, the upper part of a skull, and two teeth) upon which Dr. E. Dubois, the naturalist, bases his new species Pithecanthropus erectus, an intermediate stage between the anthropoid apes and man. Prof. Virchow contended that the four fragments did not belong to the same animal. Prof. O. C. Marsh was inclined to support many of Dr. Dubois's conclusions. Prof. Rosenberg thought that the peculiarities by which Dr. Dubois made his new species occurred in human bones, and in some few cases all of them combined. Prof. Rosenberg acknowledged, however, the great value of the discoveries, because, even if the bones were human, they proved that Tertiary man existed in Java; the origin of man being thus pushed further back toward the earlier Tertiary period.