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Page:Popular Science Monthly Volume 57.djvu/116

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POPULAR SCIENCE MONTHLY.

a peculiarly marked form, and is known there as the "Barisal guns." M. Van den Broeck calls it "mistpoeffers," or air-puffs. The most definite description of it is given in Nature by Mr. Henry S. Schurr, as he has heard it in India, where it has been observed over a wide range, but most clearly and frequently in the Baekergunge district, of which Barisal is the headquarters. The Barisal guns are heard most frequently from February to October, not during fine weather but just before, during, or immediately after heavy rain. They always sound in triplets—that is, three reports occur, one after another, at regular intervals—and though several guns may be heard, the number is always three or a multiple of three. Sometimes only one series of triplets of sounds is remarked in a day; at other times the author has counted as many as forty-five of them, one after another, without a pause. The report is exactly like the firing of big guns heard at a distance, except that it is always double, or has an echo. A number of conjectural solutions of the phenomenon have been put forth, but none of them accounts for it as a whole in any approaching a satisfactory manner.

 

Photographing Live Fishes.—A number of methods are mentioned by Dr. K. W. Schufeldt, in a paper on the subject, by which fishes may be photographed in their natural element, with natural surroundings. This can be done, even under the surface of the water, by the use of certain subaquatic apparatus. By the employment of instantaneous photography some fishes have been taken in the air, as of salmon in the act of leaping, or of flying fish in flight. Such pictures, however, illustrate special habits rather than the ordinary life of the subjects. Well-arranged aquariums afford opportunities for photographing fishes in almost every condition and position, and a command of light and situation can be had in them which is of great advantage to the operator. The specimens of fish photographs published by the author with his paper are in every way satisfactory. The spots on the sun fish, for example, are almost as clear and distinct as if we had the fish lying before us in the broad light. The photograph of the pike has afforded opportunity to correct some inaccuracies in the drawing of it as given in previous works of high authority.

 

Marine Life at Cold Spring Harbor, Long Island.—Mr. Francis N. Beach, in presenting to the Boston Society of Natural History a list of the Marine Mollusca of Cold Spring Harbor, Long Island, speaks of the locality as representing "a fairly distinct facies of molluscan life—the fauna of the oyster beds, broadly speaking. From this point of view, its homogeneity and the absence of stragglers lend it value. Probably almost every species enumerated lives on the spot where found or in the immediate vicinity. This characteristic makes the spot a good sample of actual conditions of life in that interesting transitional region where the 'Virginian' and 'Acadian' (or 'Boreal') faunas overlap. From this point of view it is, so far from being homogeneous, strikingly heterogeneous." Of the two faunas, the southern one contributes a quota rather more than twice that of the more northern one, and the increase in the preponderance of southern forms can be detected in a range of forty miles. The author concludes from his examination that, notwithstanding the well-marked character of Cold Spring Harbor as "muddy," its molluscan fauna is determined not at all by that character, but predominantly by the depth of water and by the factors included in the "inclosedness" of the place—that is, he supposes, by the temperature, the specific gravity, the percentage of organic matter, etc. "It looks as though the various species would manage somehow to be represented on almost any stretch of shore or bottom, provided only the water conditions be right."

 

Farm Homes for Neglected City Children.—The system of providing homes upon farms is represented in the last annual report of the New York Juvenile Asylum as being on the wane. While from 1880 to 1890 twenty-four per cent of the children committed to the asylum were placed in Western homes, the percentage from 1890 to 1897 was only fifteen. Among the reasons assigned for this diminution are the increase of undesirable material, chiefly of