CONTENTS - Preface - I. History and Theory of Spectroscopy - 1. Historical Review - 2. The Atom in Spectroscopy - II. Light Sources - 1. The Electric Arc - 2. The Spark - III. Spectroscopes - 1. Optical Systems - 2. Industrial Spectrographs - 3. Spectroscope Construction - IV. Spectroscopic Analysis - 1. Qualitative Analysis - 2. Determinations - 3. Quantitative Analysis - V. The Spectroscope in Mineralogy - 1. Tests Used in Mineral Identification - 2. Application of the Spectroscope in Mineral Classification - VI. Characteristic Lines of the Elements - VII. Wave-Length Table-Chart - Appendix - Conversion Table - Bibliography - Firms Selling Spectrographic Materials - Index - PREFACE - Too many chemists, mineral collectors, prospectors, and even ass ayers struggle with tedious chemical and uncertain Hame and blowpipe tests when a spectroscope would give far more prompt results. With electricity universally available, and with present day instruments and parts so low in cost, spectroscopic equipment should be in every school and laboratory. This book has been written to assist those who wish to analyze ores, minerals, alloys, and inorganic chemicals, or wish to teach others to do so. In the qualitative analysis of such materials, there is no instrument so rapid and accurate as the spectroscope, although the analyst must remain within its limits of operation. This is also true of the quantitative analysis of these materials. Although speed comes only after some experience, one may very soon acquire the necessary technique for accurate determinations. The author has attempted to point out some of the short cuts to quick spectroscopic success. Direct methods of burning samples are shown; the key lines of each element have been selected, and a new chart-table has been prepared which shows both the spacing of spectral lines and their wave-lengths. An increasing number of schools and universities have courses in spectroscopy, and many industrial plants use spectrographic equipment to speed up the solution of their special problems of analysis. The bulk and cost of spectroscopes tend to increase in geometric ratio with efficiency, and thus the price of a commercially built high-dispersion instrument is usually beyond the reach of the individual analyst. The parts necessary to make a powerful instrument are few and the essential construction is very simple. The writer believes that instructions for making effective instruments at costs so low as to be within the reach of all, will be appreciated. One section of the book has, therefore, been devoted to such instructions. Largely from his own experience, but also from the literature (see bibliography) a considerable amount of material has been arranged in what is hoped will be helpful form.