Page:Popular Science Monthly Volume 1.djvu/265

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MISCELLANY.
253

its own, even in the case of professional watermen, but such evils are aggravated for the university amateur, who has so often to proceed from hard rowing to hard reading."

PHYSIOLOGICAL ACTION OF CAFFEINE.

According to Prof. Aubert's estimate, roasted coffee contains only about one-fourth per cent, caffeine; and, if so, it is not easy to account for the exciting effect of the infusion. The action of caffeine upon the spinal cord is analogous to that of strychnine, but far weaker. It notably augments palpitation of the heart. Artificial respiration arrests its mortal effects. Caffeine also produces transitory paralysis of the pneumogastric nerve. Dr. Nasse supposes that the action of the infusion of coffee is to be attributed, not to the caffeine alone, but to empyreumatic matter.

THE DEEPEST WELL.

The Germans claim the deepest hole that has ever yet been bored into the earth. It is situated near a small village about twenty-five miles from Berlin. The boring was commenced in 1867, and stopped last year, at a depth of 4,170 feet. The diameter of the hole at the top is 15½ inches. For the first 281 feet the drill passed through solid gypsum, when a bed of quite pure rock-salt was struck, the under side of which had not been reached when the boring ceased. Careful observations of the temperature at various depths are now being made, which will be placed before the public when completed.

PHYSICAL CONDITION OF CENTENARIANS.

In a paper lately read before the London Anthropological Society on the physical condition of centenarians, Sir Duncan Gibb gives an interesting account of the examination of six persons who had severally reached the age of one hundred years. He found the organs of circulation and respiration in a condition more approaching to the prime of life than old age. None of those changes which usually mark the age of seventy were observed; and, in nearly all, the special senses were unimpaired, and the intelligence perfect, which shows at least tie complete integrity of the nervous system.

ARROW-HEADS IN NEW JERSEY.

Dr. Charles G. Abbott, writing in the American Naturalist on the "Stone Age in New Jersey," states that stone arrow-points of every variety are found at numerous points throughout the State, and that a reference to the drawings of arrow-points in Nilsson's "Stone Age in Scandanavia," and Lubbock's "Prehistoric Times," shows that whatever they have illustrated, either from the north of Europe or Terra del Fuego, is also to be met with in New Jersey. These arrow-heads are shaped from a great, variety of minerals, but those made of various forms of quartz are the most abundant.

HONORS TO PROF. DANA.

At the meeting of the Geological Society of London, for February 16th, the president, Mr. Joseph Prestwich, presented for transmission to Prof. Dana, of New Haven, what is regarded as the highest honor the Society can confer, namely, the Wollaston gold medal, which had previously been voted by the council to this distinguished scientist. Prof. Dana's labors were spoken of in the highest terms; his numerous important contributions to almost every branch of geological science being characterized as remarkable, both for learning and skill of presentation.

COPPER IN ORGANIZED STRUCTURES.

Besides its wide-spread diffusion in the inorganic world, copper is also a frequent constituent of plants and animals. It is almost constantly found in flour, straw, hay, meat, eggs, cheese, and other articles of food, and also in sea-weed. In the animal kingdom, it occurs in the blood of certain mollusks and crustaceans, and is likewise found in the blood and tissues of many of the higher animals—in proportionally large quantity in the liver and kidneys.

M. Duclaux has lately discovered it in cacao-beans. The proportion is greatest in the outer covering or husk, although the inner parts, of which chocolate is made, also contain a notable quantity. Dr. Craig, of the Army Medical Museum, Washington, has quite recently found traces of copper in oysters; not in sufficient amount, however, to account for the green color which they sometimes present.