The Chemical Gazette, Or, Journal of Practical Chemistry, in All Its Applications to Pharmacy, Arts and Manufactures Volume 14 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1856 edition. Excerpt: ...crumbly, or pulverulent mass; in dry air it does not become moist, its taste is scarcely perceptibly acid, and it may therefore very well be kept in sacks. The advantages of the process just described over those already in use are, that--1. The acid acts most powerfully upon the portion which ia most difficult of solution; 2. Only a very small quantity of sulphuric acid is required; and S. The unnecessary increase of weight is avoided, and distant transport is thus facilitated.--Henneberg-s, /ourn. fiir Landwirth-schaft, 1856, p. 107. PROCEEDINGS OF SOCIETIES. Royal Institution. April 4, 1856.--" On the Measurement of the Chemical Action of Light." By Henry E. Roscoe, Esq., B.A., Ph.D. No attempt has been made, up to the present time, accurately to measure the changes brought about in chemical substances by the action of the solar rays. The peculiar action of light on chemical bodies was first observed by Scheele on chloride of silver. Since that time the subject of the chemical action of light has attracted a large amount of attention, as the present perfection of the arts of the daguerreo-typist and photographer fully testify. Although we possess so many facts concerning the chemical action of light, this branch of science has only as yet arrived at that first or qualitative stage of development, through which every science must pass. The laws which regulate these phsenomena are unknown to us, and we possess no means of accurately measuring the amount of the decomposition effected by the light. The speaker proceeded to describe the results of a series of experiments carried on by him in conjunction with Professor Bun-sen, which had for their object, --1. To determinethe laws which regulate the chemicalactionof light; 2. To obtain a...