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Popular Science Monthly/Volume 51/August 1897/Fragments of Science

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Fragments of Science.

The Swift's Night Flight.—The curious night flight of the swifts is described in Knowledge by C. A. Witchell: "The sun has set and most of the small birds have retired for the night, though the sparrows are still noisy in the creepers on the house. Most of the swifts are flying low over the meadows, but some are in the sky, and of these a few are chasing others, and performing those magnificent swoops by which it appears that the males drive the females to their nests. Certain it is that the pursuing birds (always acting singly) chase particular individuals, whose course they follow at a greater altitude, but always with the intention of finally descending in a falconlike swoop at the lower bird, who, anticipating the attack, swerves downward and finally plunges headlong. The swishing sound produced by the descending swifts can be heard at a considerable distance. . . . At about forty minutes after sunset (whether in June or July) the group of swifts begins to whirl round and round, like a mob of rooks; but again and again the cluster breaks up in a pursuit and a mad, noisy rush across the sky. Yet the birds are gradually attaining a higher position, and their screaming becomes the less noticeable. Their wings often have a tremulous motion, reminding one of the flight of an ascending skylark. Still, there is no deliberate upward flight, only a succession of swoops and rushes, terminating at increasing distances from the ground. The birds keep fairly together, and not one descends to the houses; but it may be the cluster is joined by another group, coming you know not whence. Dusk is beginning to fall, and even the sparrows are silent, but the cries of the swifts can yet be faintly heard. The birds may now be easily lost sight of altogether, especially if there be no white, fleecy clouds high overhead to throw into relief the whirling black dots in the sky. Now is the time to use a field glass or small telescope, and, having once found the birds with it, to keep them in the field as long as possible. . . . Up and up they go, appearing smaller each moment till even the power of the glass is overcome, and the tiny specks vanish for the night. As you drop your arms wearily you find that the dusk has fallen, the bats are out, and the evening mists are rising; but the swifts must now be nearly on a level with those remote flecks of cloud which, at an immense height, are yet snowy in the sunshine."

The Light of Fireflies.—In experiments on the properties of the light of fireflies, Prof. H. Muraoka used plates of copper, aluminum, zinc, and brass of equal size, separated from the photographic plates on which they were severally laid by a layer of cardboard having a cross-shaped piece cut out of the center; wrapped the whole with three or four thicknesses of black paper, and exposed the bundle to the light of several hundred fireflies. His purpose was to learn whether the light from the insects after filtration through the black paper could penetrate the metals and affect the photographic plate, and to determine the relative transparency of the substances used. To his surprise, the parts of the photographic plate under the cardboard were most darkened, while those under the cross-shaped holes remained clear. The light of the insects seemed to behave very much like ordinary light, but, after "filtration," acquired properties similar to those of the Röntgen or the Becquerel fluorescent rays—properties apparently resulting from the filtration. Further, the filtered rays appeared to exert a peculiar action toward the cardboard—called by the author a suction phenomenon—similar to that of the lines of magnetic force upon iron. The properties of the filtered rays seemed to depend on the filtering substances, probably upon their thickness. They exhibited properties of reflection, but those of refraction, interference, and polarization were not observed, although the author believes that they exist. Their properties, generally, appear to be between those of the ultra-violet and the Röntgen rays. The insects used in the experiments had two or three rows of luminous spots on their under body; but the photographic plates were affected by the whole body as well as by the luminous spots, so that a complete image of the insect was formed when it was put upon the plate, the figure of the luminous part being, however, plainer than the rest.

Dust.—Micro-organisms are the great producers of disease, and dust is the chief carrier of micro-organisms. If there is any one ubiquitous thing, it is dust, and yet, notwithstanding its dangerous contents, it is being continually poked up, so to speak. As soon as the housemaid is up, it is hustled and dusted into the air, so that by the time the family is astir any germ which may have quietly settled in some corner where it could do no harm is floating about in the air, ready to appropriate any convenient and moist resting place, such as the human lungs or a bit of the breakfast, which will shortly carry it into one of the inmate's systems. The street-cleaning department, too, spends much of its energy in simply stirring up the dust about the streets; a little of it is carried off in carts each day, but every particle thus removed has probably been previously stirred up and allowed to settle a dozen times. The carpets and upholstery of modern houses were apparently designed as dust collectors. It is impossible to clean thoroughly a thickly upholstered sofa or chair, and almost as difficult to get a modern carpet or rug clean; these articles always contain more or less dirt, which in the case of the carpet is superficially stirred up at each sweeping. In fact, the reckless way in which house and street cleaning are handled is really appalling. Dusting should always be done with a damp cloth, and carpets cleaned by a closed sweeper well filled with wet tea leaves. The street-cleaning problem is simply a question of water supply. A thorough flushing of the streets once or twice in twenty-four hours offers a simple hygienic and thorough solution.

Pocket Gophers.—The pocket gophers, or Geomyidœ, according to G. Hart Merriam' s description, are North American animals exclusively, and most at home in the western United States and Mexico. Their whole organization is modified to suit a life underground. They are short-legged, thick-set animals, with no appreciable neck or external ears, and very small eyes. The feet are adapted to digging, the fore paws in particular being very strong and armed with long, curved claws, while the sides of the toes are lined with rows of bristles that prevent the dirt from passing between the fingers. The tail is moderately long, thick, fleshy, usually hairless, and sensitive to the touch. In working under the earth the animals loosen the ground with their upper incisors, while they keep their fore feet in active operation in digging and pressing the earth back under the body, and their hind feet in moving it still farther backward. As the dirt accumulates in its rear the animal turns in its burrow and, bringing its wrists together under its chin, with the palms of its hands held up, forces itself along by its hind feet, pushing the earth outward. All the pocket gophers have external cheek pouches, which are used for carrying food. They are great hoarders, and fill their storehouses with vastly more than they consume. The cheek pouches reach back as far as the shoulder. A captured animal filling its pouches after a meal made motions so rapid that they were hard to observe. If a piece, say of potato, too large to go in the pouch, was given him, he would grasp it with both paws and pry off small bits with his long lower incisors, then raise himself a little on his hind legs and hold the fragment between his fore paws while eating previous to putting away what was left. Small pieces were disposed of promptly; others were trimmed by cutting off projecting angles. The animal has to use its fore paws in passing food from its mouth to the pouches, and in emptying the pouches these paws are used very dexterously.

Ginseng.—This drug, which is frequently spoken of as the panacea of eastern Asia, consists of the roots of Panax ginseng, belonging to the natural order Araliaceœ, a plant indigenous to China and Japan, but chiefly occurring in Corea and Manchuria. The following account is taken from the Lancet: When full grown, the ginseng plant stands from a foot to a foot and a half high, each stem supporting a single palmate leaf. The flower is purple-colored, and in summer is replaced by brilliant red berries. The roots are gathered at the commencement of winter, and, after maceration in cold water for three days, are placed in covered vessels which are suspended over fires until the contents become hard, resinous, and translucent. The drug then appears in the form of brittle rods, often forked or many-tailed, about the thickness of the little finger and from two to four inches in length. The taste is sweetish and glutinous, recalling, in spite of slight bitterness, that of licorice. The wild plant is the most highly valued, but it is extremely rare, being worth more than its weight in gold. According to the Chinese Times, ten large sticks of ginseng and eight of medium size, weighing collectively nine ounces and one fifth, fetched, including duty, seventeen hundred and seven taels (about seventeen hundred dollars). Ginseng culture in Corea is exclusively in the hands of a few state farmers, and is most carefully supervised. The fields are surrounded by lofty barriers, while in each a watchman, perched on a platform, keeps guard night and day. The seeds are set in ridges, the tender shoots being protected from sun or storm by sheds of thatch or coarse cloth. During the first year or two the seedlings are frequently transplanted. They do not attain to maturity until about the fifth year, and, as a rule, are not culled before the sixth or seventh. The leaves are said to possess emetic and expectorant properties, but the roots alone are employed medicinally, being prescribed as a tonic in every disease that is attended by debility. It is as an aphrodisiac, however, that ginseng is in greatest request throughout the whole of the Orient. It is taken in the form of an extract or decoction, the latter mode being generally preferred. It is usually taken in the morning and at bedtime. From three to five grammes of the root constitute a daily dose, and the exhibition may be continued for a week or more. Several unsuccessful attempts have been made to introduce the drug into Europe.

Pilgrims of the Japanese Alps.—In exploring what are called the Japanese Alps, the Rev. Walter Weston found himself in a region still unaffected by European innovations; a plateau more than a hundred and twenty miles long, surrounded by mountain ridges, and known, on account of its secluded position, as "the island province." The old superstitions prevail there in full force: "Hunters burn candles and pray to the spirit of the crag they are climbing"; a black dog or white paper is a charm against the evil one; and "the drawing of 'a horse rampant' is a recognized prophylactic against smallpox." Until a few years ago women were not allowed to climb beyond a certain limit; and when the wife of one of the mountaineers ventured beyond it she was turned, they say, into a stone. Mr. Weston had the very pillar pointed out to him. But the charm is now broken, and women can climb in security. It is, however, considered sacrilegious to climb a mountain till proper parties have been sent to the top to pray the gods for good weather. The mountains are ten thousand or more feet high, of various geological character, and, being near the sea, command peculiar views. Hodekadaka is granite; Yarigstake, the highest peak after Fujisan, is of brecciated porphyry; and Fujisan, nearly two thousand feet higher than the others, is a crater. No railroad or common road enters the mountain region, though both come near it. Mr. Weston met several "pilgrim clubs" a sort of Alpine clubs having a more numerous membership and costing less than those of the West. "Every year, before the season commences, they meet and decide by ballot who shall climb the sacred mountains. . . . They also stamp their alpenstocks with the names of the mountains they have ascended." They regard their exercise as a religious one, and as they went up they chanted, "May our six senses be pure, and may the weather on the honorable peak be fine!"

The Longevity of Astronomers.—We take the following from an article under the above title in The Observatory. The longevity of astronomers has often been called attention to. The Herschels, the Cassinis, and others have been notable examples. This is all the more curious, as their vocation necessitates late hours and constant exposure to night air. The following consists, says the writer of the paper, of a portion of a list of the names of well-known men connected with astronomy who have lived beyond the allotted human span of "threescore years and ten." The ages are correct to within a few months:

Obit. Age.
Fontenelle, Bernard de 1757 100
Herschel, Caroline L 1848 08
Cassini, Count J. D 1845 97
Sabine, Sir Edward 1883 94
Mairan, De 1771 93
Somerville, Mary 1872 92
Santini, Giovanni 1877 91
Sharpe, Abraham 1742 91
Long, Dr. Roger 1770 90
Airy, Sir George Biddell 1892 90
Thalesb. c. 550 90
Humboldt, Alexander von 1859 90
Robinson, Rev. T. R 1883 90
Bouillaud, Ismael 1694 89
Rosenberger, Prof. Otto A. 1890 89
Gautier, Jean Alfred 1881 88
Biot, J. B. 1863 88
Cassini, J. D. 1712 87
Messier, Charles 1817 87
Wallis, J. 1703 87
Brewster, Sir David 1868 86
Halley, Edmund 1742 86
Schwabe, Samuel Heinrich 1875 86
Barlow, Peter 1862 86
Pingre, Alexander Guy 1796 85
Longomontanus 1647 85
Horrebow, P. 1764 85
Whiston, William 1752 85
Pritchard, Rev. Charles 1893 85
Maclear, Sir Thomas 1879 85
Button, Dr. Charles 1823 85
Dick, Dr. Thomas 1857 84
Woolhouse, W. S. B. 1893 84
Newton, Sir Isaac 1737 84
Le Monnier, Peter Charles 1799 84
Herschel, Sir F. William 1823 84
Lee, Dr. John 1866 83
Bernouilli, Daniel 1782 82
Troughton, Edward 1835 82
Gibers, Dr. William 1840 82
South, Sir James 1867 82
Le Gendre, Jean 1833 82
Nasmyth, James 1890 82
Eratosthenesb. c. 195 81
Aristarchusb. c. 280 81
Emerson 1882 81
Moestlin, Michael 1631 81
Maurolico 1575 81
Bernouilli, John 1748 81
Kant, Immanuel 1804 80
Lassell, William 1880 80
Piazzi, Joseph 1826 80
Mädler, J. H. 1874 80
De Lisle, Joseph N 1768 80
Bacon, Roger 1294 80
De La Hire, P. 1718 80

Types of the Unemployed.—Of forty-two men in a German colony for unemployed workingmen, described by Mr. Josiah Flynt in the Atlantic Monthly, mechanics and common laborers were most numerous, while others had been in various occupations, and even noblemen were represented. A third of them were boys and young men, while the majority were between thirty and fifty years of age. Two had been in the United States—one as a labor agitator, while the other had never gone a day without work here, if he wanted it. Other men were in the colony "because they had been unable to find even a bread-and-water existence." They had sought work, always in the large towns, but leaving aside the smaller places, where the farmers were asking for laborers. Most of the old men had trades, "but were too old to ply them satisfactorily." One had come to trouble through politics, another because he was unfortunate in his family life. One, who had indulged a ruthless passion for cruelty and killing, was distinguished for his devout piety. The men expressed their hostility to the church, the monarchy, the army, and the police. Very few of them were out-and-out disbelievers, but nearly all had their own private religious ideas, and were perfectly sincere in stating them. Politically they were revolutionists, republicans, or socialists. They all thought they knew what ailed the world, and what it needed for its regeneration, but it hardly ever seemed to occur to them that they had any personal responsibility in the reforms suggested. They seemed to consider themselves as something aloof from society, justified in making all manner of criticisms, but not required to look into their own failings and sins. Tramps have this same trait. They will talk for hours at a hang-out campfire about what ought to be done to make the world better, and at times with a clearness of perception and earnestness of argument that are unexcelled; but let a little personal introspection or criticism be suggested, "and a silence comes over them like that of the graveyard."

The Bordeaux Vineyards.—As described by C. L. Marlatt, in a report to our Government on wine-making in France, the vineyards of the Bordeaux district extend along the Gironde and Garonne Rivers, and their products are classed and known according to the situation of the plantations or the nature of the soil. The most famous of these tracts, that of Médoc, extends from Bordeaux to the sea and between the rivers and the Landes. This tongue of land, almost a peninsula, is entirely planted with vines, and for a distance of fifty miles and five or six miles in breadth the land is occupied by vineyards. These are separated into small communes, each of which bears some celebrated or ancient name, as Margaux, Saint-Julien, etc., and produces its distinct and well-known brand of wines. The wines vary also according to the vintages, the qualities being affected by variations of seasons. The wines as they are quoted in the market usually bear the name of some château or other. These châteaux, the fame of some of which has become world-wide, are for the most part simply country seats, in which the proprietor resides from time to time. The term château was formerly applied to old manorial residences, and the antique appearance and baronial style of architecture of some of the houses is still suggestive of this association. Oxen are generally used in the rough work of the cultivation of the vineyards, while the more delicate operations are performed by women, who in their neat dresses present a very picturesque appearance among the vines. Some of the cellars in which the wines are stored are very large, and the long rows of hogsheads in them have an imposing appearance. In them the wine is bottled, and stoppered with an especial cork bearing the name of the château. The best wines are kept here for long periods of time, in order to develop the special qualities, coming only with age, which give them their reputation.

Early Writing Materials.—Quintus Curtius is cited by Dr. Bühler, in his work on Indian-Aryan Philology, as affirming that birch bark was in use among the Hindus for writing at the time of Alexander the Great. Its employment began in the north-west, where the extensive birch forests of the Himalayas afforded abundant material, and gradually spread to the other parts of the peninsula. The oldest examples of it, says Mr. A. A. Macdonnell in The Academy, are twists found in Buddhist topes of Afghanistan and in the Bower MS. of the fifth century a. d. According to the testimony of the ancient canonical Buddhist works, leaves, probably those of the palms, were the ordinary writing material of the oldest times. The earliest example is the Horiazi palm-leaf Sanskrit MS. of the sixth century a.d., which is preserved in Japan, and of which the Bodleian Library, Oxford, possesses a facsimile. In northern India, where they were written on with ink, palm leaves ceased to be used after the introduction of paper; but in the south, where the writing was scratched in with a stylus, they are still employed. Paper was introduced by the Mohammedans, and has been very extensively used for manuscripts. The oldest Gujerat paper manuscript dates from the beginning of the thirteenth century. Neither varnished boards, such as are used in Burma for manuscripts, have been found in India, nor leather or parchment, which the regulations against impurity of materials would forbid Hindus from using. Copper plates were early and frequently used for inscriptions. They furnish a curious illustration of the narrowness of the limits of invention, in that they practically all imitate the shape either of the palm leaves or of strips of birch bark.

Arid Yucatan.—The second contribution by Dr. C. F. Millspaugh to the Field Columbian Museum, on the Coastal and Plain Flora of Yucatan, relates to a region peculiar in its biological character, and differing essentially from the surrounding regions, especially in its flora. There all plants have a desiccated appearance, due to their struggle against drought, while in the neighboring areas—Honduras, Guatemala, Chiapas, and Tabasco—the wealth of exuberant vegetation is marked. The difference is brought about partly by orographic features—the other regions having elements of mountain and ridge and large streams of which the Yucatan region is destitute, and its soil and coralline substratum being so porous that whatever rain falls quickly filters into cavities, caverns, and faults beneath the surface. Hence the only residual supply of water available for vegetation is held in the peculiar sartenejas, aguadas, and cenotes. The sartenejas are depressions in the plain, from a few ounces to several hogsheads in capacity, at the bottom of which sufficient marshy soil has been formed to retain such water as falls into them. These soon dry up after the rainy season and their vegetation lies dormant. The aguadas are simply larger sartenejas, usually of circular outline and from fifty to one hundred feet in diameter. They retain stagnant water and maintain a growth of mud plants throughout the year. The cenotes are deep, perpendicular-walled, nearly circular wells, penetrating the floor of the plain and opening into an abundant supply of clear, cool water, saturated with carbonate of lime. They are from a few feet to a hundred yards or more in diameter, and from thirty to two hundred feet deep to the water level, and prove by their frequency and extent that this great plain is as freely watered far below its surface as most countries are above. Mr. Millspaugh's list of plants collected in this region and its islands includes 418 genera and 734 species.

Owl Trees.—It is common knowledge or common supposition that owls nest in the hollows of trees; and since sentiment is turning to regard these birds as beneficial enemies of vermin rather than noxious destroyers of useful things, talk is occasionally heard of protecting and encouraging them—as Sir Montstuart Grant Duff has done. An English writer has been investigating their nesting places, and finds that they prefer pollard elms in which repeated cuttings have caused growths of gnarls and protuberances and all sorts of shapeless hiding places. In one of these trees become a habitation of birds he found the center of the crown forming a kind of platform walled round by the ruins of what should have been branches. The floor of the platform was constituted of rotten wood, leaf mold, and dead sticks, mixed with the bones and fur of "finely pulverized mice." "The bases of the branches, or what should have been branches, were hollow shells, often measuring yards across, with various holes, bulges, knots, and cracks, some piercing the sides, some making only side chambers and shelves. These caverns are the chosen home of the white owl. In one she sleeps, in another she lays her eggs, in a third she has her larder when the young owls are growing up. In another similar tree, if one be near, her husband sleeps by day; and from any one of the doors or windows she slips out and flies noiselessly across the meadow when an intruder scrambles into the crown of the old tree. There is such a labyrinth of passages in the hollow chambers that to find the nest is not easy, even when the place of the bird's exit is marked." The testimony to the service rendered by the owls during the vole plague, given before a parliamentary commission of inquiry, is declared to be sufficient to justify complete protection of them by law.

Chess Players' Vision.—The study of the psychology of the great chess players has given Prof. Alfred Binet opportunity to describe a special form of visual memory which he calls geometrical. As represented by the players, the elements of blindfold chess playing are reducible to the three principles of erudition, memory, and imagination. By imagination, corresponding to what psychologists call visualization, they represent to themselves as if they saw them the positions of the pieces on the board. It is not an uncommon faculty, but is developed to a rarely high degree in the chess player; and has the peculiar power of abstracting from the object visualized solely the qualities necessary for the combinations of the game, consisting of the reciprocal positions of the pieces and their motions. The image seen by the player is therefore an image of fixed positions and possible movements; or, a geometrical visual image. A second element of blindfold chess playing is the recapitulating memory, or the faculty of repeating all the movements in the order in which they have been played. Blindfold playing rests chiefly on the exercise of these two memories—the memory of position and the memory of recapitulation. The third element of the play, erudition, comprehends the recent memory of a game. The analysis of it furnishes a good occasion for studying the true character of what may be called the memory of ideas, and the part which former recollections play in the acquisition of new conceptions.