FOR THE USE OF SCHOOLS, ACADEMIES, AND THE LOWER CLASSES OF COLLEGES. BY JAMES RENWICK, LL. D., PROFESSOR OF NATURAL AND EXPERIMENTAL PHILOSOPHY AND NEW-YORK: HARPER & BROTHERS. 82 CLIFF-STREET. 1845. RVARD UNIVERSITY 047X192 Entered, according to Act of Congress, in the year 1840, by HARPER & BRothers, In the Clerk's Office of the Southern District of New-York PREFACE. CHEMISTRY has become a part even of the most elementary education. Its language and a knowledge of its first principles are necessary in almost every sphere of life. It has therefore been adopted as a part of the education of all our academies, and has even been introduced into our common schools; while in several of our colleges it is included among the studies of the lower classes, instead of being confined, as formerly, to the higher only. Pupils, therefore, enter upon the study of chemistry at an early age. To the intelligence of these, the larger and more complete treatises are inapplicable. They contain much more than can be made the direct object of recitation, and are better calcu lated to be used as works of reference than as textbooks. The compilation of the present work has been undertaken in consequence of the author having found, in his own experience as a teacher, the want of a manual imbodying in a plain and simple form the first principles of the science, and which, compressed into the smallest possible space, shall, notwithstand |