Excerpt from General Medical Chemistry: For the Use of Practitioners of Medicine The substance taken as the unit Of the specific gravities of solids and liquids is water. The specific weights of gases are usually referred to air as a unit; it is better, however, to adopt hydrogen as such unit (see p. When we say that the specific gravity of sulphuric acid is we mean that, volume for volume, sulphuric acid is one and eight-tenths times as heavy as water. The determination of the specific weight of a substance is frequently Of great service. Sometimes it affords a rapid means of distinguishing between two substances similar in appearance; sometimes in determining the quantity of an ingredient in a mixture of two liquids, as alcohol and water; and frequently in determining approximately the quantity of solid. Matter in solution in a liquid; it is the last object which we have in view in determining the specific gravity of the urine. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This 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.