Page:Popular Science Monthly Volume 35.djvu/886

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860
THE POPULAR SCIENCE MONTHLY.

he spent a half-year of his life as a regular professional beggar—adopting apparently all the habits and feelings of a beggar. "None the less he was a man of remarkable acquirements, being a learned Tahnudist, for those times at least a considerable mathematician, and having in middle life mastered Latin, German, French, and English, besides the various Eastern dialects of which his Hebrew knowledge was the foundation. He had evidently a very great turn for physics as well as for mathematics, and a wonderful capacity for the acquisition of languages without the slightest communication with those who could speak them, so that he knew a language fairly well of which he could not properly pronounce a single sentence." He so criticised Kant's greatest work as to excite the admiration of the author. In character "he was candid, grateful, generous, and full of kindly feelings. But he was conceited, irreverent, passionate, intolerant of the influence of others, and never really at ease among the class for which his knowledge fitted him. His study of the Talmud. . . thoroughly unfitted him for feeling the least respect for the element of authority in religion." The questions are suggested whether Maimon's vagabond tastes stimulated his intellectual restlessness, or his intellectual restlessness stimulated his vagabond tastes; whether he would have been as keen if he had been a home-stayer and steady worker, or whether it was his taste for wandering and his unsettled habits that really made his intelligence so bright. Much might be said on both sides of these questions; but the probability is, that Maimon would have been stronger and more useful, though, perhaps, less diversified and brilliant, if he had led a regular life.

An Anti-Lightning Cage.—Besides the orthodox or "gather-up-and-carry-away" system of protection against lightning there is another system suggested by Clerk Maxwell—the "bird-cage" or "meat-safe" principle. "In a banker's strong room," says Prof. Lodge, "you are absolutely safe. Even if it were struck, nothing could get at you. In a bird-cage, or in armor, you are moderately safe. . . . A sufficiently strong and closely meshed cage or netting all over a house will undoubtedly make all inside perfectly safe—only, if that is all the defense, you must not step outside, or touch the netting while outside, for fear of a shock. . . . An earth-connection is necessary as well." A wire netting all over the house, a good earth-connection at several points, and a plentiful supply of barbed wire stuck all over the roof, constitute an admirable system of defense. Points to the sky are recognized as correct; but there should be "more of them, any number of them, rows of them, like barbed wire—not necessarily at all prominent—along ridges and eaves. For a single point has not a very great discharging capacity; and, if you want to neutralize a thunder-cloud, three points are not so effective as three thousand. No need, however, for great spikes and ugly tridents, so painful to the architect. Let the lightning come to you, do not go to meet it. Protect all your ridges and pinnacles—not only the highest—and you will be far safer than if you built yourself a factory-chimney to support your conductor upon."

A Giant Earthworm.—An earthworm which, in some examples, reaches the length of six feet, is described by Prof. Baldwin Spencer, in the "Transactions of the Royal Society of Victoria," as existing in Gippsland, Australia. It is the Megascolides australis, one of a group peculiar to Australia, of which five species are known. When found at all it is somewhat abundant, and lives principally on the sloping sides of creeks. At times it is found beneath fallen logs, and may be turned out of the ground by the plow. The worm itself does not appear to leave a "casting" at the mouth of its burrow, but often lives in ground riddled by the holes of the land-crab, which forms a "casting." Hence, contradictory statements have been made about the worm's having a "casting." The presence of the worm underground may be recognized by a very distinct gurgling sound which is made by the animal retreating in its burrow when the ground is stamped upon by the foot. When once heard, this gurgling sound is unmistakable. By its rapid motion and its power of distending any part of its body at will, so as to make it fit very tightly in its hole, the worm contrives to make itself very hard to catch. It has a characteristic odor,