Excerpt from Journal of the Franklin Institute of the State of Pennsylvania, Vol. 4: Devoted to the Mechanic Arts, Manufactures, General Science, and the Recording of American and Other Patented InventionsFrom the time when it was known that the acetate of alumine was preferable, as a mordant, to alum, it was admitted, as a necessary consequence of this discovery, that the best proportions for obtain ing the acetate, were precisely those in which the two salts were most completely decomposed. And chemical analysis has shown that 100 parts of alum contain or nearly, of alumine, but of alumine require for their saturation of acid: and it will take no less than 116 parts of acetate of lead to furnish this quantity of acetic acid.We know that the common alum is composed of sulphuric acid, alumine, potash, and water, and we may also consider it as, being composed of sulphate of alumine, sulphate of potash, and water. We also know from experiment, that if a certain portion of the ace tate of lead be first added, it will become united by preference with the sulphate of alumine, and the only aim of this process be ing to obtain the acetate of alumine, it results that it is useless to employ more of the acetate Of lead than is sufficient to decompose the sulphate of alumine, as all which we add above that proportion is entirely lost.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.