No coin nor oath required. For personal study only.
Bleaching by Eleetrioity.--Dobbie and Hutcheson have experimented upon bleaching by the aid of electrolysis. For this purpose the stuff is dipped into sea water and then passed through hot rolls which are connected with the poles of a galvanic battery. In order to decompose the hypochloride which is thus formed, the cloth is drawn through diluted acid and fully bleached.--Dingler's Journal, Oct., '82.
Barometer. --Maseart has invented a barometer in which the variations of weight are shown and measured by the changes of height in a column of mercury, which is in equilibrium with the pressure of a mass of gas. The instrument has been tested under shocks of every kind to which it would be exposed in traveling in Paris, Hamburg, Stockholm, Drontheim, and TromsS. It was found to be readily transportable, and its precision did not appear t~ be inferior to that of the pendulum. It requires no other observation than that of the temperature and the level of the mercury, and the preparation can be made in less than an hour in a hotel chamber.--
๐ SIMILAR VOLUMES
Photometry by Electricity. 273 new8 of national or financial import, and tidings of joy or grief with unerring promptness. The news of yesterday in the old world, becomes the theme of conversation to-day in the new; thus completing the triumph of science, and the testimony of success to 'energy and
## Hunting by Electricity. [flour. Frank. Inst., graphite partially burnt. But, after all, two analyses of Bessemer operations pertbrmed in Germ:my prove this "mgmentation of the car-I)(m: aeeording to Kessler, after 4 minutes tile carbon passes in one operation from ?.'58 to 3"79, and ill another
Jamin--]llumination, etc. 403 a circle is drawn tangent to a straight line. He proposes to build a section of the river works, then about to be constructed upon this principle, and hopes to attain a more uniform depth of water by this means than he could otherwise expect. M. Fargue, similar to other