A LABORATORY TEXT BOOK OF PRACTICAL CHEMISTRY; OR, INTRODUCTION TO QUALITATIVE ANALYSIS. A GUIDE TO THE COURSE OF PRACTICAL INSTRUCTION GIVEN COLLEGE OF CHEMISTRY. WITH 90 ENGRAVINGS. By WM. G. VALENTIN, F.C.S. LONDON HA JOHN CHURCHILL & SONS, NEW BURLINGTON STREET. MDCCCLXXI. 193. e. 39. PREFACE. IT is with considerable diffidence that the Author brings this text-book before the chemical public. The system of chemical notation introduced by Dr. Frankland into the lecture teaching, based upon the doctrine of atomicity, and embodied in his lucid "Lecture Notes," published four years ago, necessitated a corresponding change in the laboratory teaching. The experience gained by me during several years' teaching on this system, under comparative difficulties, owing to the want of a suitable Laboratory Text-book, has convinced me that this method of classification of elements according to their atom-fixing power, is capable of simplifying the study of chemistry generally, and in a marked degree also of chemical analysis. A knowledge of qualitative and quantitative analysis is best acquired by working practically in a laboratory. Most students can, however, devote only a limited amount of time to laboratory work; and it has, therefore, been the Author's endeavour to enter only so far into theoretical considerations as was absolutely necessary to explain the laws which govern chemical changes, and to make the beginner practically familiar with the properties of elementary matter, and the most important forms of combination met with in a limited course of practical instruction. This has been kept strictly in view in arranging the |
