MUSEUM OF COMPARATIVE ZOOLOGY. 



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The following instruments are in preparation : — 



Geyser apparatus, after the models of Petersen and Andreae. 



In addition Mr. Jaggar has devoted some time to the prepara- 

 tion of photographs, lantern slides, and diagrams illustrative of 

 the work of former experimenters. 



The following papers, results of work in the experimental labora- 

 tory, are in preparation : — 



Ripple-mark, and related Geologic Phenomena. 



On the Geological Work of Yortices and Eddies. 



An Experimental Study of Glacial Delta Deposits. 



The Influence of Rate of Compression and of Composite Thrusts, 

 in Rock Deformation. 



Summer Courses in Geology. 



The elementary summer course was given in Cambridge, under 

 the direction of Professor N. S. Shaler, by Dr. G. E. Ladd. In 

 addition to the systematic instruction by lectures and laboratory 

 work, about twenty field excursions were made to localities easily 

 accessible from Boston, the most remote being Newburyport on 

 the north and Newport on the south. Lectures were given by 

 Professor Shaler on dynamical geology, Professor Davis on physio- 

 graphic geology, Dr. Jackson on palaeontology, and Mr. Woodworth 

 on glacial geology. The course closed with a written examination 

 and a practical test in field work. 



The second course in geology in the Summer School was given 

 by Professor Shaler and Mr. J. B. Woodworth. One week was 

 spent in Cambridge at the beginning in preparation for the subse- 

 quent outdoor work. The districts then visited included the Nor- 

 folk County and Narragansett basins, the Island of Martha's 

 Vineyard, and the Triassic valley in Connecticut. These districts 

 afford an exhibition of the Pre-Cambrian, Cambrian, Carbonifer- 

 ous, Jura-Trias, Cretaceous, Miocene, and Pleistocene rocks of 

 Southern New England, with a variety of secondary structures. 

 Five students took this course, three of these being registered in 

 the University during the college year. 



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