316 - Scientific Intelligence. 



the difficulty encountered in Germany in finding other deposits, 

 and the very slight amount of search for potash that has been 

 made in this country. He argues with much plausibility that 

 there must certainly be potash deposits even in the eastern 

 and central parts of the country, he points out the enormous 

 advantages of discovering and developing them, and urges Gov- 

 ernment aid for this purpose. — Jour. I. and E. Chem., 12, 837. 



h. l. w. 

 Obituary. 



Dr. Joseph Paxson Iddings died on "Wednesday morning, 

 September 8th. Although it was known that his health had 

 been failing for some time, his early death was not anticipated 

 even by his most intimate friends until within a few days of its 

 occurrence. 



Dr. Iddings was one of the most widely and favorably known 

 of American penologists and his name will ever be associated 

 with the development of microscopic petrology. He was con- 

 nected with the U. S. Geological Survey from 1880 until 1895 

 and was professor of petrology at the University of Chicago until 

 1908, since which time he had devoted himself mainly to his pri- 

 vate work, living at his country home in Brinklow, Montgomery 

 County, Md. He was a man of excellent training, a careful, 

 conscientious and philosophic worker and, since his retirement 

 from his professorship, had travelled extensively throughout 

 the principal volcanic fields of the world with a view of com- 

 pleting his studies in vulcanism and volcanic products. His 

 best known publications are: H. Rosenbusch's Microscopical 

 Physiography of the Rock Making Minerals, 1898 (a transla- 

 tion) : Rock Minerals, 1906; Igneous Rocks, 1909; and the Prob- 

 lem of Yulcanism, 1914. He was also one of the most active of 

 the joint authors of the Quantitative Classification of Igneous 

 Rocks. Numerous other of his writings are to be found in the 

 periodicals and publications of the Geological Survey, among 

 which may be mentioned the reports on rocks of the Eureka Dis- 

 trict, Nevada (Monograph XX) and of the Yellowstone National 

 Park (Monograph XXXII). 



Dr. Iddings was a man concerning whom it is difficult to speak 

 in a wholly impersonal manner by one with as strong a feeling of 

 attachment as the writer. He was not merely a geologist, but a 

 man of broad culture and a gentleman, one who was always dis- 

 posed to recognize the best in any one and overlook that which 

 was less favorable ; a clean, healthful minded man of gentlemanly 

 bearing such as made him friends wherever he went, and his 

 loss will everywhere be deeply deplored. q e0 p. Ty[ ERRILL 



John Marcus Blake of New Haven, Conn., died on September 

 21, at the age of eighty-two years. He was a man of varied gifts, 

 much interested in crystallography; his first publication in this 

 Journal was in vol. 41, up. 308-311, 1866, and the last in vol 46, 

 pp. 651-662, 1918. 



