=Longevity of Whales.=--Some light was thrown, a few years ago, upon the subject of the vitality of whales by finding one of these animals in Bering Sea, in 1890, with a "toggle" harpoon head in its body bearing the mark of the American whaler Montezuma. That vessel was engaged in whaling in Bering Sea about ten years, but not later than 1854. She was afterward sold to the Government, and was sunk in Charleston Harbor during the civil war to serve as an obstruction. Hence, it is estimated, the whale must have carried the harpoon not less than thirty-six years. In connection with this fact, Mr. William H. Dall gives an account, in the National Geographic Magazine, of a discussion with Captain E. P. Herendeen, of the United States National Museum, of cases of whales that have been supposed to have made their way from Greenland waters to Bering Strait, and to have been identified by the harpoons they carried. While it is very likely that the whale really makes the passage, an uncertainty must always be allowed, for ships were often changing ownership and their tools were sold and put on board of other vessels, and harpoon irons were sometimes given or traded to Eskimos. It therefore becomes possible that the animal was struck with a second-hand iron. =Solidification of Hydrogen.=--As soon as he was able to obtain liquid hydrogen in manageable quantities, in the fall of 1898, Mr. James Dewar began experiments for its solidification. The apparatus he used was like that employed in other solidification experiments, consisting of a small vacuum test-tube, containing the hydrogen, placed in a larger vessel of the same kind, with excess of the hydrogen partly filling the circular space between the two tubes. No solidification was produced, and the effort was suspended for a time, while the author attacked other problems. The experiments were renewed in 1899, with the advantage of more knowledge concerning reductions of temperature brought about by reduction of pressure. A slight leak of air in the apparatus was observed, which was frozen into an air snow when it met the cold vapor of hydrogen coming off, and this leak at a particular point of pressure caused a sudden solidification of the liquid hydrogen into a mass like frozen foam. An apparatus was then arranged that could be overturned, so that if any of the hydrogen was still liquid it would run out. None ran out, but by the aid of a strong light on the side of the apparatus opposite the eye the hydrogen was seen as a solid ice in the lower part, while the surface looked frothy. The melting point of hydrogen ice was determined at about 16° or 17° absolute (-257° or -256° C.). The solid seemed to possess the properties of the non-metallic elements rather than of the metals, among which it has been usual to class hydrogen.