Excerpt from Mackenzie's Five Thousand Receipts in All the Useful and Domestic Arts: Constituting a Complete Practical Library Relative to Agriculture, Bees, Bleaching, Brewing, Calico Printing, Carving at Table, Cements, Confectionary, Cookery The assay of tin ores in the liquid way was looked upon as impracticable, till Bergmann densed the following method, which is generally successful Let the tin ore be well separated from its stony matrix, b well washing, and then reduced to the most subt e powder; digest it in concentrated oil of vitriol, in a strong heat for several hours, then. When cooled, add a small portion of concentrated marine acid, and suffer it to stand for an hour or two; then add water, and when the solution is clear, pour it off, and precipitate it by fixed alkali - 13! Grains of this precipitate, well washed and dried are equivalent to 100 of tin in its reguline state, i the precipitate consist of pure tin; but if it contair copper or iron, it must be calcined in a red heat for an hour, and then digested in nitrous acid, which will take up the copper; and afierwards in marine acid, which will separate the iron. 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.