Page:Popular Science Monthly Volume 48.djvu/153

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143
FRAGMENTS OF SCIENCE.

ensued, causing the animal to rush wildly about the table, but failing to lift it into the air. In this condition any impulse, such as touching or pinching, induced a repetition of 'shamming.' After a strong impulse the shamming was prolonged, and, indeed, a direct connection was obvious between the strength of stimulus and the length of period of quiescence. This power of response to stimulus was maintained for two days, and then weak fluttering set in for some hours, followed by death. "We are forced, then, to conclude that here, at any rate, death-feigning is a purely reflex phenomenon, and that the sensory stimulus received by the surface of the body caused inhibitory impulses to arise reflexly from the ganglia of the central nerve chain, and prevented all movement of the locomotor muscles. In confirmation of this it may be mentioned that denuding the wing of its scales over any area caused a marked diminution of sensitiveness over the area so treated. Since all stages between sensory hairs and ordinary scales occur in Lepidoptera., it is not unreasonable to assume that the scales still function as tactile end organs in spite of their modification subserving decorative purposes."



MINOR PARAGRAPHS.

Navigators and other writers of the sixteenth and seventeenth centuries speak of a pretended art of controlling the winds which was claimed by Finnish and Lapp wizards, who sold wind in packages consisting of a cord with three knots. "If the first knot is untied," Grimm says, "the wind becomes favourable; if the second, a still better wind is secured; but a tempest inevitably follows the undoing of the third knot." Speaking of Greenland, Nightingale says: "The sailors of the north are so credulous that they often buy these magical cords; and they believe that, if they follow the instructions concerning the way of untying them, they will get whatever sort of wind they want." Like accounts are given by Leems and Scheffer; and the belief is referred to by Shakespeare in Macbeth.

A summary is published in the journal Himmel und Erde of reports made to the Bureau of Statistics in Berlin, which seem to show that cases of damage from lightning are regularly increasing. Thus while, according to Prof, von Bezold, the average number of accidents per year in Bavaria was thirty-two from 1833 to 1843, it has gone up from period to period till in 1880-'83 it was one hundred and thirty-two; and, while in 1855 one hundred and thirty-four persons were struck by lightning and seventy-three of them were killed, the number struck thirty years later was one hundred and eighty-nine, of whom one hundred and sixty-one were killed. The increase is ascribed to a variety of causes, among which are the use of electricity in industry; changes worked upon the earth's surface by the cutting away of woods, drainage, etc.; and the fouling of the air with coal smoke.

As presented by General Greely in a paper at the recent International Geographical Congress, arctic exploration has passed through three important phases. The first was a commercial phase, when the discoveries of Chancellor gave rise to the Muscovy Company and the institution of trade between Great Britain and Russia. The second was the geographical phase, which culminated in the beginning of the present century, and under which an unparalleled wealth of geographical results has been harvested. The third phase of scientific investigation has been prominent in later years, and now dominates, so that no expedition can command support unless its aim is scientific. Altogether, it can be proved that arctic industries have contributed some $12,250,000,000 to the wealth of the world.

Herr S. A. Andrée presented his plan for a balloon expedition to the north pole before the recent International Geographical Congress. He advises that the balloon should be capable of carrying three persons, necessary instruments, and provisions for four months; that it should be so impermeable that it can be kept afloat thirty days; that it be filled somewhere in the arctic region, and be to a certain extent steerable. The start should be made in July, as early as the weather would permit, on a clear day with a brisk south wind blowing, so that it may go north quickly. The central and most inaccessible part of the polar region should be