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Page:Popular Science Monthly Volume 46.djvu/299

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are brought under strict discipline, and obey their keeper's call with extraordinary intelligence. The mandarin duck, a smaller variety, is reared for its beauty, and is prized as an embellishment to the artificial lakes with which the grounds of the wealthy are adorned. By virtue of their repute for conjugal fidelity a pair of them are introduced into wedding processions. The eggs, preserved by a peculiar process, after which they will keep for several years, form an important part of mandarin dinners. Geese, pure white, and of great size and majestic carriage like that of the swan, are bred; turkeys for foreigners and gold and silver pheasants are raised, and the cormorant is domesticated and trained to a wonderful degree of intelligence for fishing. The birds are taken out on the lakes and rivers in a small boat, one man to every ten or twelve cormorants. They stand perched on the sides of the boat, and at a word from the man they scatter on the water and begin to look for their game. They dive for the fish, and then rise to the surface with the catch in their bills, when they are called back to the boat by the fisherman. As docile as dogs, they swim to their master and are taken into the boat, when they lay down their prey and again resume their labor. The use of incubators in hatching eggs has been known and practiced in China for several hundred years, as it was also in ancient Egypt. The apparatus is described as very primitive; but the men engaged in the business know exactly the day when the young ducks or chickens will come forth, and are prepared to receive them.



It is the habit of centipeds to carry their young, clasped by means of their legs, to all parts of the under side of the body, though generally the young are clustered in dense masses. When the young are thus bunched together the body is coiled upon itself at that part; and the contrast between a centiped in this position, says Mr. J. J. Quelch, who describes the centiped's method in Nature, and a scorpion carrying her young upon her back, just as a small opossum does, is a very marked one.

The sumpitans or blowpipes of the Jakuns living on the Serting River in the sultanate of Johore are manufactured from a very long-jointed, straight variety of bamboo, which is generally carved and traced with many rude devices. The darts consist of thin splinters of wood about a foot long, having a plug of pith at the blunt end. The point is as sharp as a needle, and is covered with a black, resinous substance, which is in many cases extremely poisonous. Monkeys and other small animals die from its effects almost immediately; on man and the larger animals its action is less rapid, but quite as deadly. The poison is known to the Malays as ipoh.

An active discussion was had in the British Association on the question of the criterion by which a flint should be regarded as the work of man or of Nature. With regard to the ruder forms of what some extreme anthropologists include among Palæolithic implements opinion was much divided; as it was also on the point as to how far the position in which such implements, even when recognized as artificial, are found can be accepted as an indication of their age. The moral suggested by the discussion is that many flints have been accepted as the handiwork of man on the most inadequate evidence, and that there is still much doubt as to whether man existed in the British islands in preglacial times.

Photographic records taken with the aid of the capillary electrometer of electric currents produced by speaking into the telephone were exhibited by Mr. Burch in the British Association. The letter z produced a complicated curve in which oscillations of current lasting only one three-thousandth of a second were visible with a lens. The speaker said that the electromotive force produced in using the ordinary telephone amounts to about one tenth of a volt; but with emphatic syllables it may rise high enough to produce electrolysis.

The question whether the intensity of the radiation of heat by the sun is affected by its condition as to spots has been studied by M. R. Savelief, of Kiev, in the light of observations made in the spring and the fall of the years 1890, 1891, and 1892. The results point to an affirmative answer, the radiation being greater as the sun-spot activity augments. A variation in one series of the experiments is interpreted as indicating that the increase is dependent, not so much on the absolute number of the spots as upon the intensity of their evolution; or it may mean that it is immediately consecutive on their diminution. The meeting of the British Association at Oxford was attended by 2,311 persons, several hundred more than attended last year's meeting; and the receipts were £2,175. Appropriations of £1,100, or about £100 more than usual, were made for grants for research. The committee of recommendations proposed that Section D be called zoölogy instead of biology; that a separate section be consti-