REPORT ON THE GEOLOGICAL DEPARTMENT. 



By J. D. Whitney, Sturgis- Hooper Professor of Geology. 



During the whole of the past year, instruction in Lithology was 

 given, three times a week, by Mr. Wadsworth, to one special stu- 

 dent, and to two undergraduates who had elected this subject 

 among those offered in the post-graduate scheme of instruction, 

 having previously qualified themselves for lithological work by 

 special mineralogical study. As this appears to have been the 

 first attempt in this country to give systematic instruction in Lithol- 

 ogy, according to the modern methods, some details of the course 

 followed may with propriety be added. The instruction consisted 

 of lectures upon the macroscopic and microscopic characters of 

 the rocks and their constituent minerals, and also of field and 

 laboratory work. Besides the study of the laboratory collections, 

 each student had assigned to him a separate district, which he 

 was to map, studying the characters and relations of the rocks, 

 and collecting the necessary specimens. Of the rocks thus 

 collected, the student was required to make thin sections, and 

 to examine them microscopically, writing a thesis upon the whole 

 work. It was intended that the course should be sufficiently thor- 

 ough to fit the student for practical field and laboratory research. 



Mr. Wadsworth also continued his investigations of the Cali- 

 fornian rocks, of which the thin sections had been made during 

 the previous year, as mentioned in the last Report. Written de- 

 scriptions of several hundred specimens were prepared, with the 

 intention of publishing, in due time, a full account of the volcanic 

 rocks of the Pacific coast. The chief results of this investigation, 

 so far as the same had been completed up to February last, were 

 embodied in an abstract published in the Bulletin of the Museum, 

 with the title, " On the Classification of Rocks." 



The larger portion of the time of the Sturgis-Hooper Professor 



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