Weather-Glass, or Storm-Glass. - An ingenious contrivance of this nature has lately been announced by Wiegleb, in Germany; and the invention of it is like wise claimed by Mr. Francis Anone, of High Holborn : it consists of a glass tube, containing a liquor that holds in solution a compound substance, the transparency, or turbid appearance of which, indicates the changes in the atmosphere. Thus, if the weather promise to be fine, the solid matter of the composition will settle at the bottom of the tube, while the liquid is pellucid ; but, previously to a change for rain, the compound will gradually rise; the fluid will continue transparent; and small stars will be observed moving or floating about the glass.
Twenty-four hours before a storm, or very high wind, the substance will be partly on the surface of the liquid, apparently in the form of a leaf; the fluid, in such case, will be very turbid, and in a state resembling fermentaion.
During the winter, small stars being in motion, the composition is remarkably white, and somewhat higher than usual, particularly when white frosts, or snow prevail. On the contrary, in the summer, if the weather be hot and serene, the substance subsides closely to the bottom of the glass tube.
Lastly, it may be ascertained from what point of the compass the wind blows, by observing that the solid particles adhere more closely to the bottom, on the side opposite to that, from which the tempest happens to arise. - This instrument has been satisfactorily employed both at sea and on shore: being small, portable, and tolerably exact, it may often serve as a substitute for the more bulky and expensive contrivances in common use. - See also Barometer.
Weather-Glass. - In this article, we have alluded to a comG position suggested by Wiegleb; and which may serve as a chemical barometer. He directs 2 drams of camphor to be pulverized; with purified nitre, and sal ammoniac, half a dram of each. These ingredients are then dissolved in 2 oz. of proof-spirits, in a cylindrical glass ; and the orifice is covered with paper, or a thin piece of bladder, perforated with a needle. On placing this vessel in a moderate temperature, all the phenomena formerly stated, will take place according to the changes of the weather.