The student is referred to the Text-book of Mineralogy, prepared mainly by Mr. E. S. Dana, for a detailed exposition of the subject of crystallography after Naumann's and Miller's systems, and also of optical mineralogy and other physical branches Of the science; to the Manual of Determinative Mineralogy and Blowpipe Analysis by Professor george J. Brush, for a thorough work on the use of the blowpipe, and complete tables for the determination Of minerals; and to the author's Descriptive Mineralogy and its Appendixes for a comprehensive treatise on all known minerals.