Popular Science Monthly/Volume 32/December 1887/Popular Miscellany

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Popular Science Monthly Volume 32 December 1887  (1887) 
Popular Miscellany
 

POPULAR MISCELLANY.

The Proposed Monument to Audubon. — At the recent meeting in New York of the American Association for the Advancement of Science, the fact that the remains of the great naturalist Audubon lie in an obscure and little-visited portion of Trinity Cemetery, New York city, and that his tomb is unmarked by any distinguishing monument, was brought to the attention of the members. The demands upon the time of all in attendance at that meeting were so great, that no action was taken by the Association, although the most lively interest was expressed by individual members, and the propriety of marking the resting-place of the founder of American ornithology by a suitable monument was appreciated. The Audubon plot in Trinity Cemetery will probably be disturbed by the continuation westward of One Hundred and Fifty-third Street. The trustees of the cemetery have, with commendable liberality, assigned the Audubon family a new plot, close to One Hundred and Fifty-fifth Street, in full sight of Audubon Park, and near the end of Audubon Avenue, when this shall be continued from the north, and are in hearty cooperation with the monument enterprise. At the first autumn meeting of the New York Academy of Sciences, a committee was appointed to solicit funds and make all arrangements for a monument. It consists of Professor Thomas Egleston, of tlie School of Mines, chairrnan; Profess- or Daniel S. Martin, of Rutgers Female College, and Dr. N. L. Britton, of Columbia College. This committee has organized, with Dr. Britton as secretary and treasurer, and is now ready to receive subscriptions, which will be properly acknowledged. Checks should be made payable to X. L. Britton, treasurer, and post-office orders should be drawn on Station H, New York city. The committee estimates that from six to ten thousand dollars will be required to erect and engrave a shaft worthy the memory of America's first naturalist, and, while confident that this amount will be forth- coming, desires to have interest taken in the project by scientists in all departments throughout the country.

The Hills and Valleys of Cincinnati.—

Professor Joseph F. James, in a study of the topography of Cincinnati, describes the valley, with its two ancient parallel river- terraces, in which the business part of the city is built, as girt with a line of hills, rising from three hundred and ninety-six feet above low-water in the Ohio River, or eight hundred and twenty -c'ght feet above the sea, the height of Mount Adams, to four hundred and sixty or eight hundred and ninety-one feet, the height of Mount Au- burn. The hills were originally rounded at the top, but have been so marred by the de- structive agencies of city "improvements," that they can hardly be recognized. There still remain, however, the great drainage- valleys, which have for ages carried the water from the north, south into the Ohio River, None of them, except Mill Creek, which occupies part of the ancient channel of the Ohio, are of any great extent, and this is one fact tending to prove the former insular character of the suburban parts of Cincinnati. Four of these valleys are men- tioned, besides Mill Creelc. While they, with their attendant heights, have added greatly to the picturesqueness of the city, they have, at the same time, been taken advantage of in the building up of the suburbs. The heights have been utilized for dwellings, while the valleys between have proved in- valuable for streets. The tracing of the divide which separates the Ohio River drain- age from that of Mill Creek, is an interest-

ing study. It pursues a general northeast and southwest direction, and can still be followed in quite a definite manner for a part of its course. In two cases instances arc observed of two ravines heading up close to one another on both the south and north sides of the divide; and these lend illustration to a remark that has been made by Captain Button, that in mountainous countries the ravines form a series of am- phitheatres close to a narrow divide which remains sharp in all stages of erosion. The Rev, G. F. Wright, of Oberlin College, has found that the southern foot of the conti- nental glacier crossed the Ohio near Point Pleasant, about twenty-five miles above the city, and recrossed it at Aurora, Indiana, blocking the course of the stream for about fifty miles. Professor I. C. White has esti- mated the height of this dam at six hun- dred and forty-five feet above low-water in the river. From the absence of any traces of glacial drift upon the hills, the author doubts if it could have been so high. Be- sides enlarging upon the beauty of the situ- ation of Cincinnati, which no man can ques- tion. Professor James claims for it that, situated on part of the oldest dry land (Cam- brian) in the Western world, its site "can boast of an antiquity which puts to shame many more renowned cities," its rocks being "hoary with the age of countless centuries," while the soil of New Orleans is "yet satu- rated with its baptismal shower"; they were gi-ay with moss when the Devonian site of Louisville was deep under the ocean; when the sub-carboniferous of St. Louis was as yet scarcely even in process of formation; and they vastly antedate the Rocky Mount- ains and the Mississippi.

A Central Astronomieal Agency.—In a paper on "The Extension of Astronomical Research," Professor Edward C. Pickering, of Harvard Observatory, calls attention to the fact, that while the net results of astro- nomical research have been of enormous pecuniary value, in certain cases large sums of money have been expended with little or no useful return. Striking instances may be mentioned of observatories without prop- er instruments, large telescopes idle for want of observers, and able astronomers unpro- vided with means of doing useful work. The object of his paper is to suggest a way in which this waste of resources may be in part remedied, and in which money may be most advantageously employed for the ex- tension of astronomical knowledge. This way is through the establishment of a cen- tral agency to which funds might be sent, to be expended on observatory or other work, so as to attain the best results, independ- ently of all local and personal conditions. No institution appears to be better adapted for such service than Harvard College. It is financially strong; the management of the funds intrusted to it has been excel- lent; and its officers know perfectly well what are the requirements of scientific work.

The Boomerang.—Several German ob- servers have been studying the boomerang for the discovery of the secret of its curious course of flight. Dr. II. Landois, of Miin- ster, from intercourse with a group of na- tive Australians who were exhibited there, has found that there are larger and smaller boomerangs. The larger ones are slender crescents, about sixty centimetres long, five and a half centimetres wide, and one cen- timetre thick; plane on the lower side, convex on the upper side, pointed at either end, and sharpened toward the edges. The lower end is cross-grooved, to aid in hold- ing it. The careful manner iu which the savages manipulated the weapon, trying its shape, testing its qualities, and scraping it down, is significant of the importance they attach to its having exactly the right curva- ture. The wood of which the instrument is made is an extraordinarily heavy Australian iron-wood; and the only tools used in mak- ing it are sharp stones and pieces of glass. The smaller boomerangs are bent at an angle of 45°, but are in other respects conformed to the larger ones. An exhibition of boomerang- throwing revealed a degree of strength in the natives which was in astonishing contrast with the thinness of their forms. They took the weapon in their right hand, with the flat side downward and the concave side for- ward, and with a run and a shout, threw it by a short jerk about one hundred yards up into the air. It flew away in a straight line, then turned to the left, and retui-ned in a curved line back to the thrower, whirling around constantly and whizzing unpleasant-

ly. The curve which the weapon describes in its return is not a screw line or a spiral, but is more like a figure 8. The savages seemed able to control their instrument, even when wind interfered to complicate its course. Once the projectile went astray, and, coming in contact with a gentleman's hat, cut it off as cleanly as a razor would have done. Ilerr Hermann Froebel, of Wei- mar, who seems to be a manufacturer of toy-boomerangs, as he speaks of having made eleven thousand spi=!cimcn3 of the article, believes he has discovered the mys- tery of its shape. It is not a crescent or even curvature, but must have a kind of nick or sharper curvature in the middle, with the two arms of unequal length, in the proportion of about four to five. The arms should not be of the same thickness, but the longer one should be pared down so as exactly to balance the shorter one. The correctness of these principles may be veri- fied by adding a very little to the wqight of either arm, or by slightly shortening the longer one. The instrument will then no longer answer its peculiar purpose any bet- ter than if it were only a common stick. The peculiarity of the motion of the boom- erang is due to the difference in the length of the arms, by the operation of which a divergence from the circular is imparted to its curve of rotation. The remarkable feat- ure of the whole matter is that such sav- ages as the Australians should have been able to discover the peculiar properties of this form and apply them. The fact shows what extraordinary powers of observation the people of nature possess. The attempts to give a philosophical explanation of the trajectory of the boomerang variously com- pare it with the caroming of a billiard-ball, the sailing of a piece of paper or card-board in the air, and the flight of birds.

What is Graphite?—Graphite is not lead, as its names plumbago and "black- lead" would seem to indicate, nor is it a carburet of iron, as some works of scientific pretension still call it. Except that some impure specimens contain about as much iron as ordinary clay, it is the purest form of carbon, the diamond not excepted. Pro- fessor W. Mattieu WilUams believes that it is nothing else than extremely finely divided charcoal or soot; and reasons upon the sub- ject as follows: The hand-rails on the stair- cases of the Metropolitan Railway stations, after some use, become coated with a deli- cate film of graphite or "black-leaded." The same is seen, but more faintly, on suburban hand-rails, but not at all in rural stations. "Whence comes this graphite film? Why is it developed as we approach the center of London, reaching its maximum in the most densely populated and sootiest regions of the metropolis? My answer to these ques- tions is, that it consists of a selection of the very finest particles of London soot. The hands of passengers in rubbing along these rails conduct a debtor and creditor trans- action. There is soot carbon on the hands and soot-carbon on the rails, as on every- thing, animate or inanimate, that is exposed to a London atmosphere. Some of the soot- particles on the rails are brushed off by the hands, some rubbed down and smeared on the wood; some are abstracted by the hands, and some are contributed by the hands as additions to the smearing. It is obvious that in such proceedings the coarser par- ticles are those that will be brushed off or carried away, while only the very finest, the impalpably minute particles, will adhere as a black, varnish-like, unctuous film to the hard wood." So, when the coarsest lamp- black or ordinary soot, the finest vegetable- black, and powdered plumbago, are rubbed upon paper, the appearance of the fine black will be found to be intermediate between that of the other two substances.

What the Edible Birds' Nests arc made

of.—Xaturalists have not been able to de- cide of what material the edible birds' nests are composed. Some have regarded them as made of pure animal secretions; others believe that algae enter largely into their composition. Mr. E. L. Layard has sug- gested that the nests of the first quality, or those which arc made early in the season, are made of secretion, but that later on, if the first nests are destroyed, the birds can not replace them by this secretion alone, and have to use extraneous substances to help in the construction. Mr. J. R. Green, of the Physiological Laboratory, Cambridge, has examined specimens of the nests of vari- ous qualities, and finds them all to become

alike gelatinous in texture on soaking, and made up of laminae aflSxed by their faces to one another. Some nests of inferior qual- ity showed the presence of alga-, but neither in their mode of disposition nor in the quan- tity did they confirm Mr. Layard's view. The scanty amount and rregular position of the algse would be better accounted for on the theory of their being accidental constituents. The nest- substance gave no micro-chemical reactions that could connect it at all with cellulose, so that it could not be formed by the partial digestion of the algaj and regurgitation of the resulting matter. On the other hand, it did give very striking evidence of its close relationship with the substance mucine described by va- rious authors, and well known as a product of the animal body.

Cameos.—Cameos are made from pieces of sea-shell, of which, as every one must have noticed, while the outside is often rough and unseemly, the interior is perfectly polished, and sometimes of a bi-illiant color. The shells, which are usually of a species of Cassis and Strombus, natives of the West In- dies, are chosen on account of the thickness and hardness of the layers, of the contrast of color between them, and of the presence of knobs on the exterior surface which ren- der it possible to work in relief. When a cameo is begun, a piece of the shell, rather larger than the ornament is intended to be, is cut out and affixed to a holder by a kind of coarse sealing-wax. The inner surface of the shell is of course the lowest, and on the gray outside the master draws a rough outline of the design, and places the work in the hands of an apprentice, who, by means of a file, reduces the knob to the requisite height, removes all the gray matter that Ucs outside of the boundary-lines, and dresses the whole of the irregular surface. In this condition a cameo looks like an irregular piece of chalk rising out of a small plate of colored glass. It is now returned to the master, who again draws the design in pen- cil upon it; and from him it passes to an- other apprentice or workman, who brings out the design with a burin. In late years it has become the fashion to have cameo- portraits taken, but the likenesses, to which the artist usually manages to give a classical turn, are said to be "often striking, always clever, and generally abominable." The great fault of most modern cameo-cutters is an excessive fondness for detail.

Gronnd-Water and Health.—Mr. Bald- win Latham, C. E., declares, as the conclu- sion derived from eleven years of investiga- tion, that there is generally a parallelism between the conditions of health and the volume of ground - water. The years in which there has besn a large quantity of ground-water present have invariably been the healthiest years, while those in which there has been a small quantity have invari- ably been the most unhealthy periods. As a rule, the lowness of the ground-water in- dicates the future health, and not the state of health at the particular time of lowness; that is, the unhealthy period, as a rule, follows the period of low water, the de- gree of lowness indicating the intensity of future disease. In some instances an un- healthy period runs concurrently with the period of low water, but in all these cases there is clear evidence that percolation has begun before the unhealthy period comes on. These results, which are con- firmed by observations made at Paris, differ from those obtained by Professor Petten- kofer, at Munich, in that he there found typhoid fever and low water concurrent; in all other respects they agree with his. There is also clear evidence, derived from experience in England, that the lowering of the subsoil water by artificial means produces a tendency to the development and dissemination of typhoid fever. It is clear, however, to the author's mind, that ground- water itself has no influence, cither for good or evil, upon health, but that the low- ness or highness of the water in the ground is the index of conditions which greatly influence the health of all communities. We have periods of abundance of water, and periods of low water, with both healthy and unhealthy conditions. Ground - water has been shown by Professor Pettenkofer to be chemically more impure in periods of high water when the conditions were favorable to health than when there is a low state of the ground-water and a condition unfavor- able to health. The records also show that we have periods when rain has started into existence malignant diseases; while, on the other hand, we have similar heavy rain- falls accompanied by a high state of public health. The records clearly point out that it is not one circumstance alone which pro- duces disease, but that there are at least three factors concerned in the matter, espe- cially in the case of typhoid fever, viz.: the elements which produce disease, such as a polluted state of the ground; the conditions which are necessary for the development of disease, such as a period of dryness of the ground in those regions which water usually occupies, combined with a compara- tively high degree of temperature; and con- ditions which will lead to the spread of the disease, such as the probable influence of a storm or rain in driving impurities out of the ground into our water-supplies, or through the instrumentality of ground-air passing into our habitations, and its recep- tion by a population which is in a condition to receive such germs of disease. If any of these conditions is absent, diseases like ty- phoid do not occur. It has been pointed out by Professor Pettenkofer that in those districts in which the rivers are held up at uniform levels by rains, the conditions are favorable to health, and cholera seldom be- comes epidemic. This is corroborated in great measure by the state of health at sea- side resorts, which being at the natural out- flow for ground-water, and owing to the uniform height of mean tide-level are placed in a condition favorable to health.

Hints in Object-Teaching.—Mrs. Sarah J. Hale, in a little book on "Infant-School Management," gives some excellent precepts for interesting children in subjects of study and making them at home in them. "In every case," she says, "the teacher must bring plenty of illustration to bear upon the lesson. In natural history the real ani- mal, or a picture, should be exhibited, and if possible something that it furnishes us with, as, for instance, the fur of the otter, the shell of the tortoise, the quills of the por- cupine. The teacher should also carefully provide herself with pictures of animals which afford strong contrasts to those with which she is dealing, as well as those which bear some general resemblance to it, that she may exercise the discriminative as well as the assimilative faculty of her pupils. In all object-lessons, various specimens of the object should be produced for examination and description; the little ones themselves must do the main part of the latter under the teacher's guidance, for these lessons are not only to enable the children to form new ideas, but they are also intended to train them in giving expression to such ideas. The teacher must make good use of the blackboard, and should practice drawing objects, so that she may illustrate with fa- cility and precision any particular point of her lesson which can be so illustrated. All the materials, pictures, diagrams, etc., which the teacher provides from time to time should have their place in the school mu- seum ready for future needs, and the chil- dren should be encouraged to bring contri- butions to such a museum, particularly such as the lessons they receive may suggest."

Artificial Production of Minerals.—Ac- cording to M. Fricdcl, of the French Asso- ciation, experimentation in the artificial pro- duction of minerals was suggested by the observation of the crystalline products acci- dentally formed in the metallurgic furnaces. Mitscherlich and Berthier took it up, and it has been advanced by a considerable num- ber of experimenters. MM. Fouque and Michel L6vy, by melting certain silicates and then exposing the vitreous mass to a lower temperature than that of fusion, have reproduced the identical minerals formed in the eruptive rocks, including the anorthite and labradorite feldspars, amphigene, py- roxene, peridote, and magnetic iron. While the granites have not been produced as such, their constituents—quartz and ortho- clase and albite feldspars—^have been ob- tained in crystals. The first essays at re- producing the zeolite groups of minerals have been made by De Schulten, by heating the silicate of soda in tubes of aluminous glass. Spinel and corundum, among pre- cious stones, were long ago produced by Gaudin, Ebelman, H. Sainte-Claire Deville, and Caron; and MM. Fremy and Feil have more recently prepared the ruby in large crystalline masses, which possess all the properties of the natural mineral except the susceptibility for cutting. A new ad- vance seems to have been made in produc-

ing rubies, for artificial stones of fair di- mensions have been met with in the trade, which, though not as bright and transparent as the natural gems, have their hardness, density, and optical properties. The dia- mond alone appears to have so far resisted all attempts at reproduction.

Somnambnlism.—The phenomena of somnambulism and their connection with the nerve-centers have not been satisfac- torily accounted for. They probably de- pend primarily, says the "Lancet," upon a directing impulse of sensory origin. Some of our actions often become by practice so nearly automatic that partial sleep or stupor does not arrest their unconscious perform- ance. In somnambulism the intellect and the controlling will are torpid, while the sensori-motor man whom they should gov- ern is awake and active. As in dreams the intelligent sensorium is alone drowsily ac- tive, with possibly a noticeable tendency to restless movement, so there may be oth- er states of dreaming, in which the centers of motion are stimulated to a more power- ful but unconscious action. Partial coun- teractives to somnambulism may be found in throwing off worries, and in the proper regulation of evening meals.

British Colonial Wines.—Among the features of the Indian and Colonial Exhi- bition held last year in London, was the de- partment of colonial wines, in which the Australian wines played a prominent part. The soil, climate, and other Australian con- ditions differing from those to which Euro- pean vines are subject, have stamped these wines with an individuality, in consequence of which they can never become exact sub- stitutes for those of Europe. The lighter qualities of the Australian wines are be- lieved, however, to be suited for consump- tion in England, where the commoner wines of France might be found too cold and thin for ordinary use. The phylloxera was dis- covered in Australian vineyards in 1877, but was checked in a very short time by the ap- plication of summary and effective measures. The Cape of Good Hope is capable of pro- ducing immense quantities of wine per acre, amounting in some vineyards to nine times the average in France, and four times in Australia. But the growers seem to have become careless as to the treatment of their vineyards and the quality of the wine they produce, and the exportation has fallen off. A few samples of wines were exhibited in the Canadian court. In late years much attention has been bestowed in Canada upon grape-growing and wine-making; and, in 1881, four million pounds of grapes were raised in the Dominion, of which nine tenths were grown in the province of Ontario. The wines exhibited were found sound and pleasant, and enjoy a local reputation; but they were hardly known outside of the Dominion before the Exhibition.


Qualities of Sewage-Farm Milk. — Dr. Carpenter, of Croydon, denied, during a recent discussion in the Society of Arts, that the milk produced on a farm irrigated by sewage was contaminated or less wholesome than other milk. When he became acquainted with the Croydon sewage-farm, they had difficulty in getting rid of the milk, because of the prejudice against it. But by judicious management the prejudice was worn out. The speaker knew, from personal experience, that the children who took the milk were never troubled with any of those illnesses which were said to be due to bad milk, and there were never any complaints of the milk, which was delivered once a day, becoming sour. That was a proof of its power of being assimilated by the body, and that it was of a perfectly desirable character in point of health, he knew from examination of the families who took it. They had now no difficulty in Croydon with regard to the disposal of their milk from the sewage-farm.