Page:Popular Science Monthly Volume 1.djvu/656
THE POPULAR SCIENCE MONTHLY
that we are often unable to give a reason for its following a particular course, and the action of this mighty force seems to us like a mere freak. Such ideas, are, however, entirely wrong; and we may accept most implicitly the statement that the flash will always take the easiest path, and it must be our duty to determine beforehand what this path shall be, and to make it so easy and so perfect that the resistance will not cause the electricity to produce the slightest mechanical violence.
The Academy of Sciences in Bologna has announced that a prize of 1,200 lire (about $240), the "Aldini Prize," will be awarded to the author of the best scientific experimental essay on galvanism or dynamic electricity. Essays intended for the competition must be sent in between July 1, 1872, and June 30, 1874, and must be written in Italian, Latin, or French. They must be either written or printed; but, in the latter case, must Dot have been published previously to the two years above mentioned. Each essay is to bear a motto, and to be accompanied with an envelope stating the name of the author. They must be addressed to the Perpetual Secretary of the Academy of Sciences of the Bologna Institution.
Harvey, the discoverer of the circulation of the blood, is at length to be honored by the erection of a national memorial. The townsmen of his native place, Folkestone, have resolved not to allow the tercentenary of his birth to pass unnoticed, and it has been decided that a bronze statue, if possible, of a very superior class, shall be erected to his memory. A committee is in progress of formation in London to assist the Folkestone committee, and public scientific bodies and individuals are being asked for aid and coöperation.
Repeated spectroscopic measurements made last year by Profs. Zöllner and Vogel, in Germany, show that the velocity of rotation of the sun on its own axis is at the rate of 660 miles an hour.
Dr. Angus Smith gives a good rule for ascertaining the amount of carbonic acid in the air of houses: "Let us keep our rooms so that the air does not give a precipitate when a 10½ ounce bottle full is shaken with half an ounce of clear lime-water," a sanatory regulation which can easily be carried out.
A French doctor has recently been making some curious experiments as to the effect of alcohol on fowls. The birds took to dram-drinking with evident delight, and many an old cock consumed his bottle of wine a day, so that it became necessary to limit the allowance. They all lost flesh rapidly, more especially those which drank absinthe. Two months of absinthe-drinking was found sufficient to kill the strongest cock or hen. The fowls which indulged in brandy alone, lasted, however, four months and a half, while the wine-bibbers survived for ten months. Their crests also swelled to four times the original size, and became unnaturally red.
A German naturalist answers the question, how many eggs a hen can possibly lay, as follows: The ovary of a hen contains about 600 embryo eggs, of which, in the first year, not more than 20 are matured. The second year produces 120; the third, 135; the fourth, 114; and in the following four years the number decreases by 20 yearly. In the ninth year only 10 eggs can be expected, and thus it appears that, after the first four years, hens cease to be profitable as layers.
It is proposed by the United States Signal Service to institute, during the present season, a series of observations, in connection with balloon ascensions, upon temperature, barometric pressure, currents, etc., in the higher atmosphere. Sergeant Schaeffer, one of the corps, has been designated for the service, and is now preparing for the work, which is to be begun in the neighborhood of Boston.
The experiment of introducing salmon into the Delaware River, though a failure last year, through the death of the larger portion of the young fish while on their way from the hatching-houses to the river, has this year been attended with success; owing, it is said, to the hatching being done near the river, whereby transportation for long distances was avoided.
According to Prof. Gould, electric waves travel through the Atlantic cables at the rate of between 7,000 and 8,000 miles per second; or, about half as fast as they traverse the wires suspended on telegraph-poles.
A hundred thousand young shad have been put into Lake Champlain during the present season, for the purpose of determining whether they will five and multiply when confined exclusively to fresh water.