Page:Popular Science Monthly Volume 16.djvu/741

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"Exactly at the place where the skin seems to be moving backward, a pair of ribs expands. This action enlarges or puffs out the body, and by stretching loosens the skin at that place. In this movement both ribs in the pair act at the same time, just as the two blades of the scissors open together. Now comes a second movement of this pair of ribs, in which action the two ribs alternate with each other. One of them—say the one on the right side—is pushed forward and made to slip out of and in front of the constriction made by the swelling, when it immediately works backward, that is, against the neck of the double receding skin. Now the left rib makes a like advance, and in a similar manner presses backward." Thus, for every backward movement of the inverting skin, there are three rhythmic movements: First, the expansion of one pair of ribs; second, the swelling of the body at that spot; and, third, the pushing back of the skin by the alternate action of each rib. "The cast-off skin is presented inside out, so that every scale is now seen on its under or concave side, and this is also true of the eye scales. To all this there is one exception; the last scale of the tail is a hollow pyramidal or four-sided spike. . . . When the shedding has reached this scale a sharp shake of the extremity is sufficient, and the uneverted spike is left inside of its everted skin." The entire process witnessed by Professor Lockwood took only half an hour, but he says that if a snake is in poor health the casting of its old clothes takes longer and is a much more difficult matter.

A New Food-Fish.—Among the many remarkable results given in the last report of the United States Fish Commission is the discovery of a very important food-fish, entirely unknown to our fishermen. It is a large flounder, the Glyptocephalus cynoglossus, and is known in Europe as the pole or craig. But in Europe it is far from being plentiful, and is highly esteemed as having some of the best qualities of the turbot, especially the presence of that delicious gelatinous fat along the fins. Much of the work of the Commission has consisted of dredging in water of various depths. While trawling with a beam at distances from five to ten miles from the shore, the fish was discovered, and in great quantities; so great, indeed, that a fifteen to twenty minutes' drag would sometimes furnish as many as five hundred pounds of the fish. The reason that this fish has not been known hitherto is due to the fact that the beam-trawl, the only apparatus by which it can be taken, is not used by our American fishermen, as it is by those of Europe. The mouth of this large flounder is so small that a hook small enough to be swallowed would not sustain the weight of the fish. There is every reason to expect that this fish will soon take its place in our markets. The Commission have also brought to light new species of food-fishes i. e., of fishes supposed hitherto as only living in the colder waters of Greenland and Scandinavia. These, too, American enterprise will yet bring to our markets; but, to do so, fishing must be carried on two or it may be three hundred miles from the coast.

Improved Method of diving and staying under Water.—The apparatus now in use for supplying air to divers engaged in submarine operations is both cumbrous and unsafe, the air-tube limiting the movements of the diver, and, by its liability to become entangled and crushed, causing a risk that the supply of air for respiration may be cut off altogether. A new method, in which these drawbacks are escaped by dispensing entirely with the air-tube and pumps, has been invented by a Mr. Fleuss in England, and lately exhibited at the Royal Polytechnic Institute in London. Dr. B. W. Richardson was given an opportunity to closely watch its operation, and from his description in "Nature" we glean the following account of the experiments: The peculiarity of the method consists in the diver's taking a full supply of air-food down with him, which dispenses with pumping, no help being needed except a signal-man and cord. Mr. Fleuss is both inventor and diver. He descends into the water in an ordinary diver's dress. It consists of helmet, breastplate, and common water-tight armings and leggings. On his shoulders he carries a weight of ninety-six pounds, and on his boots twenty pounds. A light cord is attached to the helmet for signaling to the person above. Before the mask is closed and the helmet adjusted, an "ori-nasal mouthpiece," with