Popular Science Monthly/Volume 50/February 1897/Fragments of Science

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Fragments of Science.

American Man in the Ice Age.—Very important evidence has been found during the past year of the existence of man in North America during the Ice age, or at least the latter part of it. The two chief items, coming from different parts of the country and established by the evidence of different observers working independently, are of sufficient force to make the conclusion exceedingly probable. First, we have the discovery by Mr. Volk, reported to the American Association by Prof. Wright and enlarged upon by Prof. Putnam, of argillite implements in the undisturbed glacial gravel near Trenton. The excavations, carried on during two years by Mr. Volk, in such a manner and through such formations that mistake was practically impossible, revealed a disturbed upper layer of sand and gravel, in which were implements of flint and argillite, and beneath this an undisturbed layer, compact and distinctly stratified, in which only implements of argillite were found. The opinion, reached by Prof. Wright and Prof. H. Carvill Lewis fifteen years ago, assigning this formation to "a period when the land stood one hundred and fifty feet below its present level, and when the cold waters from the melting glacier bore ice rafts which dropped their bowlders," is confirmed by Prof. Salisbury in his last New Jersey Geological Report, who holds that "it seems certain that the formation (Jamesburg) was produced during the submergence of the area which it covers," and that it has been only slightly eroded, contrary to the view of Prof. Chamberlin that the glacial deposit was an older one than this, and has suffered great erosions. The fact that only argillite implements were found in the lower stratum, while both flint and argillite are found in the layers above, contradicts the theory that they drifted down through cracks, root holes, etc., for in such drifting there could have been no selection of one kind of implements and exclusion of the other kind. The second piece of evidence was presented by Prof. E. W. Claypole, who described the finding of neolithic axes in digging a well in the blue till, twenty feet below the surface, at New London, Huron County, Ohio. The account of the workman who found the implements, given in full, describing the formations through which he passed in the digging, and confirmed by Prof. Claypole's personal inspection of the premises, is so distinct as apparently to leave no room for doubt. The circumstantial evidence sustaining his testimony is of the most convincing character. The passage from the yellow till into the blue till, and the occurrence of occasional strata of gravel, are characteristic of the glacial deposits of northern Ohio; and the axe had been subjected to oxidizing agencies characteristic of the deeply covered strata of that immediate vicinity. The Trenton discovery is interpreted as showing that there was a clearly marked succession of human occupancy in the Delaware Valley, in which, from the sole use of argillite implements, a transition occurred to the use of flint and jasper in later times; while in the Ohio discovery the conditions were such as apparently to exclude every supposition but that of the contemporaneous age of the implement with the formatiom in which it was found.

Nature Study in the Chicago Schools.—A plan for systematic outdoor or field work in connection with Nature study, to be carried on by the pupils of the public schools of Chicago, has been reported by a committee of sixty teachers which was appointed in May, 1896, by the Chicago Institute of Education. The features of the plan may perhaps be best understood by indicating the duties of the subcommittees which the general committee has instituted to care for its various special features. First is the executive committee, the purpose of which is to devise ways and means for carrying the whole into effect and to second the efforts and work of the other subcommittees. A committee on maps will prepare maps of the environs of Chicago to assist the pupils and teachers in a systematic study of the country at a convenient distance around the city; these maps to comprise large maps, each including only one of the most conspicuous geographo-geologic features, and smaller maps showing details—the location of the specific features of interest. The maps already made by Prof. T. C. Chamberlin, and kindly offered by him, will be used as the basis of this work. A committee on syllabi is to prepare printed outlines and suggestions which will intelligently and economically direct pupils and teachers in their consideration of the different areas and subjects chosen for study. The syllabus should not be compiled information, but should simply suggest the problems that are furnished for study by each area and indicate lines and methods of investigation. A fourth committee will look in the libraries after the books that may be useful to the pupils engaged in Nature study and available for their use. A committee on instruction and school exhibits will make themselves acquainted with the work of Nature study in the schools and with the teachers engaged in it, and make monthly reports to the committee of sixty of what is actually being accomplished, and will establish at some suitable place a permanent exhibit illustrating the character of the work. A committee of public information will see that all these things are made known and kept in mind. A committee on transportation will try to interest the railroads, etc., in the scheme, and to secure convenient facilities and privileges for the transportation of pupils and parties going out to fields of Nature study. Arrangements will be made for frequent trips of small numbers rather than for larger excursions at longer intervals, which might give the affair too much the air of a picnic. Hence it is suggested that only the pupils of one or two rooms be sent out at a time, under the immediate supervision of their teachers. A committee on finance and a conference committee are also instituted for the purpose indicated by their titles. It is anticipated by the committee of sixty that, when once under way, this plan will be expanded to include every department of school work.

Spitzbergen Explored.—The principal geographical work of the Conway expedition to Spitzbergen was the first crossing of the island, from Advent Bay to Agardh Bay. The country traversed was mapped, its geology was examined, and collections were made of its plants and animals. Afterward the whole expedition sailed northward to the Seven Islands, and through Kinlopen Strait and across Olga Strait to near King Charles Island. An attempt to complete the circumnavigation of Spitzbergen was blocked by ice. The highest peak in the island was ascended. The land animals observed were the bear, arctic fox, and reindeer, of which the last are abundant. Birds are individually numerous, but of few species. All the twenty five recorded species were observed, except the snowy owl, and one unrecorded species was seen. The flora is remarkably uniform, and the influence of height has less effect upon it than situation and season. The species found on the mountain summits in the middle of the summer were the same as those observed on the coast at the beginning of spring. As the season advanced, the species first found in flower on the lowlands and in sheltered valleys were succeeded by another set; but at any time it was only necessary to seek exposed and barren positions, or to climb above the snow line, to find the first flora still in flower. Spitzbergen offered better opportunities for geological than for zoölogical or botanical research. One of the main temptations it offers the geologist is a magnificent opportunity for the study of glacial action; for there, says Mr. J. W. Gregory, of the expedition, we may see marine and land ice working side by side. The inland glaciers are very different from those of Switzerland, especially in having no névé fields. All the snow that falls on the collecting ground at the head of the glacier turns to ice on the spot. Cases of the formation of typical bowlder clay by land ice were easily found; so, likewise, were instances of the uplift of material through ice. The glaciation of Spitzbergen was solely due to a local ice action. No evidence was found of a great polar ice cap.

Care of the Lawn.—An interesting little article in Garden and Forest on lawn and grass infesting insects contains some valuable information for the suburban householder. Land cultivated in one kind of crop for many years successively tends to attract all the different kinds of insects that feed upon it. In some localities where onions were grown in times past with excellent results the onion maggots now make it impossible to raise a crop. In many parts of New York State wheat culture had to be abandoned for a time because of the ravages of the Hessian fly. Farmers have long known that after land has been in pasture for a few years, or has been mowed, the grass "runs out." They accept this fact, and act upon it without much questioning as to just what this running out consists of. In many cases it is simply because the land has become so thoroughly infested with grass-feeding insects that the roots are no longer able to support a growth. Insects are not confined to farms or farm lands; they occur wherever plants are grown in cities and villages, and are troublesome in the back yard, in the kitchen garden, to the shade trees, and even to the little patch of lawn in front of the house. The more extensive the lawn and, in a general way, the better kept it is, the more attractive it is to insects. Insects of almost all orders are found in grass lands, and, as there are few grass plots in which there is not also some clover, insects infesting this plant are also more or less abundant. It is always a matter of interest to determine what is causing the injury, but, after all, the important question is, What can we do to check it? On lawns, where the object is to keep the grass as long a time as possible, one of the simplest measures is frequent cutting and rolling. This has a tendency to drive off the lepidopterous insects that may be among the grass, and to prevent the laying of eggs. The grass should be always kept well fed; but no barnyard manure should be used: all insects do very much better in a soil containing much vegetable matter, and are least at home where mineral fertilizers are constantly used. Lawns should be fed almost entirely with mineral fertilizers, nitrate of soda being used to furnish the necessary nitrogen, and kainit or muriate to furnish the potash. The fertilizer should be applied just before a rain. Where land is badly infested and there is poultry about, it is a good plan to dig up the sod and turn the chickens in for a few days. They will, if the soil is turned over two or three times, pretty thoroughly dispose of the bugs. A kerosene emulsion is fatal to the insects and does not injure the plant roots.

The Advantage of Elective Courses.—The Hon. T. W. Higginson, referring in the recollections of his life which he is now publishing in the Atlantic Monthly to the time when he was secretary of the College Natural History Society at Harvard, observes that "in looking back on the various reports written by me for its meetings, it is interesting to see that this wholly voluntary work had a freshness and vigor beyond any which I can now trace in any of the ‘themes’ of which Prof. Channing thought so well. There is no greater mark of the progress of the university than the expansion of the electives to include the natural sciences. My own omnivorousness in study was so great that I did not suffer much from our restricted curriculum; but there were young men in my time who would have graduated in these later days with highest honors in some department of physics or biology, but who were then at the very foot of the class, and lost for life the advantage of early training in the studies they loved. Akin to this modern gain and equally unquestionable is the advantage now enjoyed in the way of original research. Every year young men of my acquaintance come to me for consultation about some thesis they are preparing in history or literature, and they little know the envy with which they inspire their adviser; that they should be spared from the old routine to investigate anything for themselves seems such a happiness."

Forests and River Flow.—Mr. C. C. Vermeule observes, in a report of the State Geological Survey on Forestry in New Jersey, that in estimating the relation of forests to the flow of rivers we should not consider the points of extremely high and extremely low water, but should look for the beneficial effects in the stages which prevail during the months of an ordinary dry period. "The soil and subsoil of a watershed," he says, "hold a large amount of water, which is fed out as drainage, in the form of springs and seepage, to the stream during dry periods. It is a matter of common observation that at such times rivers continue to flow when the rainfall is much less than the evaporation, and indeed for long periods when there is no rainfall at all. Anything which tends to increase the amount of water which is held in the ground, and to regulate its discharge into the streams, tends to give a larger flow, and to shorten the periods of very low water in the streams during droughts, and with this increased capacity of the ground to absorb rain come also less frequent floods. Humus in the forest forms a great sponge, and of itself holds a large amount of water, while it and the inequalities caused by tree roots, etc., tend to prevent the water flowing over the surface, and the roots of the trees provide channels by which the water percolates into the subsoil readily. In this way the forest will easily absorb a larger amount of water than open lands. A high state of cultivation also has a tendency to increase the capacity of the ground to absorb water, because of constant loosening of the surface and the facilities provided for ready drainage. In this way cultivation, like forests, tends to render floods less frequent, but the effect of the drainage of the soil is that the ground water absorbed is fed out more rapidly to the streams during the early months of a dry period than is the case in forests; consequently the ground water is sooner exhausted and the duration of the low stages of the rivers during protracted droughts is thereby lengthened. Barren watersheds offer less capacity for absorption of rainfall. There is no humus or other matter on the surface to retain the rain, and the ground becomes hard and resists free percolation."

Long-Lived Seeds.—M. Casimir de Candolle said, in an account in the British Association of experiments dealing with latent life in seeds, that seeds retain their germinating faculty for very long periods of time if kept dry and protected from all external influences which would produce changes in their physiological condition. The question as to what is their physiological condition during the period of rest is an interesting one. It is possible to conceive them as absorbing oxygen or as giving off carbonic dioxide. If the latter process takes place, the carbon must be supplied from the tissues of the seed itself. In that case would the seedlings produced from these seeds be normal? The author had raised perfect seedlings from seeds known to have been kept more than a hundred years. A remarkable instance of the length of time seeds may be preserved was afforded where, on clearing away heaps of rubbish which had been undisturbed for a long time in a silver mine in Greece, the ground over which the heap had lain became in a short time covered with a mass of plants, of which the seeds from which they sprang could not have been there less than fifteen hundred years. An Irish agriculturist in the audience said that certain fields in Ireland, which had long lain undisturbed, when plowed, produced an extraordinary crop of corn poppies. He thought that the physical texture of the soil would probably account for the long period during which the seed must have lain dormant. It seemed that in hard, closely packed soil seeds could remain in the resting state, but that they would assume their vital condition as soon as the soil was loosened. Another gentleman said that this power of seeds to germinate after a dormant period threw light on the glacial theory, since the seeds might possibly have remained buried in the quiescent state and then have germinated after the flow of ice had reached farther south.

Uses of Sawdust.—The most usual and extensive use of sawdust is probably as an absorbent on floors and in spit-boxes, but it has found many other economical applications. Compressed with pitch or with its own intrinsic resin if it be very resinous, it forms excellent kindling blocks; it may be burned as a fuel in specially prepared fireplaces. Fuel blocks are made by compressing it with various substances. An artificial hard wood is mentioned as formed in this way. At some factories it is distilled for purposes of lighting and the ammoniacal by-products. Oxalic acid is made from it by the process of Capitaine and Herlings. It forms a valuable litter for stables, and has fertilizing qualities of its own. Eggs are preserved by being carefully packed in it. With albumin, liquid paste, alum, bichromate of potash, or molasses it makes excellent briquettes; with cement, lime, or gypsum, a material for constructions; and with slaked lime, an excellent mortar. Mixed half and half with sand and clay, a material for partition walls and ceilings is formed. Sawdust is, therefore, a very useful material.

First Uses of Gunpowder.—The invention of gunpowder is shown by Mr. Oscar Guttmann, in his book on the Manufacture of Explosives, to have been most probably an evolution. The Greek fire of naphtha, mentioned by early European and Arabian writers, is believed to have been a composition containing niter, sulphur, and charcoal. Marcus Græcus, who wrote in the tenth century, gives a composition for charging rockets and crackers closely approaching that of modern blasting powder. This receipt is quoted by Albertus Magnus, and another one, not so clear, is given by Roger Bacon. None of these writers, however, speak of the use of such substances in any way like the firing of projectiles from guns; on the contrary, they all describe crackers and bombs or maroons, and say that these were discharged into towns from ballistæ or catapults or mangonels for the purpose of setting fire to them. Mr. Guttmann has found, however, in the Wardrobe Accounts of King Edward III of England, an entry between A.D. 1345 and 1349 giving credit to one Thomas of Roldeston for the king's work for his guns, for nine hundred and twelve pounds of saltpeter and eight hundred and eighty-six pounds of live sulphur. This seems to confirm the tradition that guns were used by the English at the battle of Crécy in 1346. Mr. Guttmann decides that Berthold Schwartz invented this use of gunpowder about 1313; if so, Schwartz must have been very young at the time, or else have lived to a very great age, for the date of his death is given as 1384.

French Mushrooms.—Mushroom-growing in France is a matter of ancient history, and the variety of mushrooms is infinite. The industry originated in a peculiar way. When the French began to make beds for their melons they noticed that large numbers of mushrooms would suddenly appear on the little mounds. They proved as profitable as the melons, but a crop could not be depended on. A number of investigators went to work to discover methods by which a fairly certain and regular crop could be obtained. They have partially succeeded, and the result is an industry very profitable to all concerned, and a consumption of mushrooms in France which is now something enormous. The mushroom loves a cool, damp place, and light has a decided effect upon its color, sunlight turning the surface to a reddish brown. It is for these reasons that it is usually cultivated in caves. In the department of the Seine there are over three thousand of these subterranean truck gardens, most of them deserted stone quarries. The people who cultivate them are said to practically live underground, and are called champignonistes. The beds are made as follows: A dry and clean place near the mouth of the cave is selected. The spot is covered with manure, which is allowed to lie undisturbed for several days. The manure is then thoroughly worked over, all foreign matter being removed, and then beaten and pressed down into shape. After about a week the process is repeated and the beds are watered. At the end of another week the surface will be brown and fermentation very active. At this stage the first turning must be repeated, when the mass is again allowed to rest three days. It should then be soft to the touch, but leave no moisture upon the hand. The temperature requires to be carefully watched, and the first heat of fermentation must be allowed to pass off before the blanc or spawn is sown. After the spawn is planted the beds are covered with a thin layer of prepared earth called goptage, kept well watered, and in about forty days the mushrooms will appear. A bed will with proper attention produce a continuous crop for three months. The seed, spawn, semence, or blanc (mycelium) is usually supplied by the market gardeners from old melon beds. It is sold in the shape of a brick or cake, which, if placed in a dry, airy place, preserves its vitality for several years. The annual crop of mushrooms in France is valued at about two million dollars.

Caviare in Russia.—In Russia fish plays a very important part in the economy of life. On fast days, of which there are so many, it is an indispensable article for the whole nation, and on other days many of the people, who are too poor to buy meat, depend on fish as their only animal food. Russia's numerous rivers and extensive coast line make fish a cheap and common food there. The most valuable products obtained from fish in Russia are cod-liver oil and caviare; the latter coming mainly from the sturgeon. The United States consul at St. Petersburg is given as authority for the following description of the preparation of caviare: The roe is taken out of the fish, and the egg bags in which it is inclosed are removed by rubbing the mass on a sieve; the eggs pass through the meshes, while the skin does not. When fish are in the first stage of decomposition, the egg skins get so soft that they can be readily separated from the roe, and from these the low grades of caviare are made. The caviare is next placed in brine. The difference between the so-called fresh caviare and the ordinary material put up for keeping or export consists in the longer or shorter time it is allowed to remain in the brine, and also on the strength of the latter. Immediately after the eggs have been rubbed through the sieve, they are put through the brine, and as soon as they are deprived of the superfluous salt, are placed in tin jars or cans and small wooden kegs, and the so-called fresh caviare, which is high priced, is ready for market. The cheaper kind is cured in the brine and then put into linen bags and pressed. This is called pressed caviare. During ten months of 1895 Russia exported 4,658,448 pounds of pressed and 613,904 pounds of fresh caviare.

Venomous Fishes.—In many seas, especially those of the tropics, are found fish provided with a poison apparatus, which consists usually of a spine or spines more or less erectile in character, and connected with a poison gland. Prof. James D. Brunton gives an interesting account of two of these fishes, the Trachinis draco and Scorpœna scropha. They are only poisonous as a serpent is poisonous—i. e., by wounding; their flesh is good and wholesome. Although the fish differ widely in appearance, yet the poison produces the same effect. The Trachinis draco is a hand-some fish, not unlike a trout in general appearance. Upon each of its gill covers is situated the spine, connected with its poison gland through a duct formed by the combination of a groove in the spine and a very thin membrane, which covers the latter almost to its point. When the spine enters a resisting body, the membrane is pushed back, allowing the poisonous secretion free access to the wound. The gland is small, with nucleated colorless cells secreting a transparent fluid. The Scorpœna, on the other hand, is an unattractive-looking fish, squat of body and having a large, misshapen head. It may attain a large size, and is called by the French fishermen "le diable." The special organ in this fish is connected with the first three rays of the dorsal fin, the duct being formed as in Trachinis. There is also a spine on each gill cover connected with a poison gland. The effect of a wound from either of these fish is quite a serious matter. At the moment of puncture only the sharp prick is felt. In a few minutes, however, the part commences to burn and itch, and then becomes acutely painful. These pains increase in violence and extent. Then a feeling of suffocation is felt, and pain over the heart. From this time commence those cries of anguish which can always be recognized as caused by the acutest torture and fear. The dies are continuous, and beads of sweat stand on the brow. Flashes of light pass before the eyes, and the pulse is found to beat intermittently. Finally, delirium and convulsions supervene, which may pass on to collapse and death, or may, after lasting for many hours, gradually subside, leaving a malaise which is very difficult to get rid of. The point of puncture soon shows the results of intense irritation, and may eventually become gangrenous and necessitate amputation. The treatment is practically the same as that for a snake bite. The poison approaches that of the serpent in character, being alkaloidal, very quickly decomposed, and intensely rapid in action. It is secreted in larger quantities at the spawning season, and is most active in the male fish. On coasts where these fish abound it frequently happens that bathers are poisoned by stepping on one of them, the Trachinii being especially fond of concealing themselves just under the sand in shallow water.It would be of interest to know whether Dr. Calmette's snake-bite antitoxin is also efficient against the venom of these fishes.

Baku.—A very interesting account of Baku, the great petroleum center in Russia on the Caspian Sea, is given by W. F. Hume. Its growth, it seems, has been almost Western in rapidity. What was an insignificant town of fourteen hundred inhabitants thirty years ago, is now a flourishing city of over one hundred thousand souls whose population is still rapidly increasing. Two causes have combined to bring about this rapid growth: First, its magnificent harbor, and, secondly and chiefly, its proximity to the main area of naphtha supply, which already rivals that of America in productiveness. Several attempts were made to start refineries in this district, the first by the brothers Doubinnin in 1823, but until 1859, when M. Kokareff founded the Baku Petroleum Company, none of them were successful. In 1865 the first refinery was established in Baku itself, and so rapidly did the industry develop, that in 1873 the town was in danger of becoming entirely absorbed by the distilleries that rose on every hand, while the black, dense, and acrid smoke from the naphtha-fed furnaces poisoned the atmosphere. The nuisance became such a serious one that the whole industry was moved outside the town (by an edict of the Government, which is Russian). How intolerable it had become, may be inferred from the fat that the sole firing material for the furnaces was the refuse oil, and no smoke-consuming appliances were employed; not only the buildings but the whole surface of the ground became coated with a thick layer of soot, while the roads were almost impassable, owing to pools and ponds of oil. The city received the name, Tchornoia Gorod (black town), which still clings to it. Through the use of a smoke-consuming device the present factory district is quite free from soot, and is hence called the white town. Baku is a commercial center, but most undesirable for residential purposes. It is subject to heavy dust storms, rainlessness, intense heat, and there is an almost entire absence of vegetation and fresh water. The only garden is the so-called Alexander II, maintained at great expense, the shrubs and trees being planted in imported soil. The spot of chief interest about the town is the plateau of Balachani-Sabountchi, situated about eight miles to the northeast of Baku. Here are located the great petroleum wells. Viewed from a distance the tall, closely set, truncated towers erected over the wells look almost like a pine forest. These pyramids consist of a wooden boarded framework, and are easily removable when the bore becomes exhausted. The Baku district is so saturated with naphtha oils that there is an ever-present danger of serious fires through the ignition of the hydrocarbon gases, which escape not only from the bores but through every fissure and cleft in the soil, and, although every possible precaution is taken, many disastrous fires have occurred.

A feature of considerable interest is the ancient temple of Zoroaster, which for twenty-five hundred years was the sacred resort for pilgrimage of the Guebers or fireworshipers of Asia. Although, owing to its importance as a commercial center, Baku at present almost monopolizes the petroleum industry in southern Russia, it is but one of many important oil fields in this district.

Life in the Coldest Country.—The coldest region of the globe, that of Werkojank in Siberia, where the lowest temperature of -90° F. has been observed, and the mean of January is -48° F., is inhabited by about ten thousand five hundred persons of the Jakut and Lamut races. In a large part of the region, according to the representations of Mr. Sergius Kovalik in the Bulletin of the Geographical Society of Irkutsk, the air is so dry and winds are so rare that the intensity of the cold is not fully realized. Farther east there are sometimes terrible storms. In the summer time the temperature sometimes rises to 86° F. in the shade, while it freezes at night. The latter part of this season is often marked by copious rains and extensive inundations. Vegetation is scanty. There are no trees, only meadows. The people hunt fur-bearing animals, fish, and raise cattle and reindeers. It requires about eight cows to support a family, four being milked in the summer and two in the winter. The cattle are fed hay in the winter, and are allowed to go out occasionally when it is not too cold, their teats being carefully covered up with felt. Milk is the principal food, occasionally supplemented with hares, which are quite abundant. The houses are of wood, covered with clay, and consist of one room, in which the people and their animals live together. The wealthier classes are better provided with lodging and food. The people are very hospitable, but excessively punctilious concerning points of honor, such as the place at table.