Page:Popular Science Monthly Volume 9.djvu/141

Rh of rotation. Near the magnet, attached to the rotating arms, is suspended another magnet, which oscillates as the attached magnet presents alternately its north and south poles. This oscillation makes and breaks an electric circuit, which, by a wire of any required length, is connected with a recording Morse machine moved by clockwork. Each revolution of the rotating pith-balls is thus recorded by a punch of the Morse on a strip of paper, and so a register is kept of the amount of light falling at any place.

A Mountain of Granite.—The "Stone Mountain" of De Kalb County, Georgia, is described in the American Journal of Science by Mr. E. Hillyer. It is a solid, bald mass of granite, from 1,500 to 2,000 feet in height. The northeast side is perpendicular, unbroken, and smooth; the northwest side is inclined so as to be of easy ascent; while the west and southwest are so steep as to be barely accessible. On the inclined surface the rock breaks off in layers, a few inches to several feet thick, which structure may be due to shrinking in cooling, and to atmospheric influences, together with solar heat. The rock is perfectly homogeneous, with no trace of stratification—a pure whitish granite. There is no doubt that below the surface lamination a piece could be quarried out a quarter of a mile in length, if man could command the means. This granite exists over a wide region of country, and is much used for building-purposes.

Rattlesnakes and their Bites.—In the course of some notes on the rattlesnake, published in Forest and Stream, Dr. J. W. Bailey, of Albany, asserts that this serpent is the most sluggish of the snake family. It never strikes unless in self-defense, excepting just before and after its winter sleep. Of course, the rattlesnake's idea of self defense is rather broad. Thus, if a person step upon it by the purest accident the snake will make no allowance, but strikes the intruder on the spot. To strike, however, it must be in close coil, with its head erect. It is capable of springing only a little more than half its length, unless it be lying on an inclined plane; then, by supporting itself entirely on its tail, it can spring much farther. Hogs attack the rattlesnake with impunity, the effect of the poison being probably neutralized by a thick layer of adipose tissue. Dr. Bailey is able to contradict, from his own experience, the statement that serpents do not move about at night; he has often, when riding by moonlight seen them gliding through the grass. The author says that, when the venom of a serpent has entered the circulation, all remedies are unavailing. He has seen a freshly-killed chicken split open and applied to the wound, with good results. In such cases the flesh of the chicken turns green and putrid where it comes in contact with the virus. The most certain remedy, however, is whiskey or brandy used in large quantities—say a quart—immediately. Intoxication is not exhibited until the poison has been counteracted. Sweet-oil, taken in doses of several ounces, is also effectual. Sportsmen camping in Texas are accustomed, after pitching their tent, to stretch around it a hair lariat. The short hairs irritate the snake's belly as he attempts to cross the lariat, and he retreats.

Cause of Monstrosities.—In the course of a discussion of the subject of "monstrosities," in the Detroit Academy of Medicine, Prof. Armor, of the Long Island Medical College, who was present, presented some ingenious views, which may be briefly stated as follows: Monstrosity is commonly referred to "arrest of development" or to "abnormal development." But what is the true cause? Prof. Armor answers: 1. Something deficient or abnormal in the generative matter from which the fœtus is developed. This generative matter he looked upon as representative; there is not a tissue, structure, or form, that is not represented in it, so that deviation from the normal type may be impressed at the very instant of conception. The next point was the faithful transmission of acquired structural peculiarities, when once fully established. Finally, it was suggested that the discussion of this subject bears directly upon the great question of evolution: the strongest and fittest survive; weak parts of the organism atrophy and die—they cease to be seminally represented. 2. The