AMOS PEASLEE BROWN. ix 



fied,"^* which was used by his classes at the University. Part II. of 

 this work was entirely rewritten, while Part III., on '•' Physical De- 

 terminative Mineralogy," was wholly original and reflects Brown's 

 views on the importance of sight identification of minerals. 



In 1904 Brown began work upon what was to prove his great- 

 est contribution to science,^^ a piece of research, the far-reaching 

 importance of which has perhaps not even yet been fully appre- 

 ciated. Dr. Edward T. Reichert, professor of physiology in the 

 medical department of the University of Pennsylvania, had begun 

 in 1902 some investigations as to the differentiation and specificity 

 of corresponding proteins and other vital substances in relation to 

 biological classification and organic evolution. He had come to the 

 conclusion that the hemoglobins of animals offered excellent pos- 

 sibilities in this line of investigation and also that their characters 

 could best be compared and their relationships ascertained through 

 a study of their crystallography. " Not being an authority in the 

 science of crystallography," wrote Dr. Reichert, " I associated with 

 me in 1904, one of my colleagues, Professor Amos Peaslee Brown, 

 upon whom has fallen that portion of the work which demanded 

 the services of an expert crystallographer." The enormous amount 

 of work that Brown contributed to the undertaking can thus be 

 readily appreciated by anyone who consults the portly volume, em- 

 bodying the results of the investigation, which was issued in 1909 

 by the Carnegie Institution of Washington, under whose grant the 

 prosecution of the work was made possible. Several preliminary 

 reports on the progress of their work were issued by Professors 

 Reichert and Brown,^*' one of which was presented at the general 

 meeting of the American Philosophical Society, in the spring of 

 1908. The hemoglobin investigation involved the crystallization and 



1* " Mineralogy Simplified." Third edition, Philadelphia, Henry Carey 

 Baird & Co. ; London, Sampson Low, Marston Co., Ltd., pp. i-xxvii -j- 1-383, 

 1901. (Fourth edition of the same with further additions was issued in 1908.) 



15 " The Crystallography of Hemoglobins," by Edward Tyson Reichert, 

 M.D., and Amos Peaslee Brown, Ph.D., Carnegie Institution of Washington, 

 No. 116, 4to, pp. i-xviii -|- 1-338, with 100 plates, 1909. 



16 Yearbook of the Carnegie Institution for 1907, p. 218 (1908). Proc. 

 Soc. Biology and Medicine, 1907-1908, V., p. 66. Proc. Amer. Philos. Soc. 

 XLVIL, 1908, pp. 298-301. 



