30 



b. Three albums of miscellaneous views taken on the way 

 to, and in Greenland. Individual pictures labeled. 

 Those in which trees appear were taken at Cape Breton 

 Island and are to show some remarkably perfect bars 

 and wave-built shore lines of several kinds. Numerous 

 pictures of floe ice and icebergs, Esquimaux, Esquimaux 

 houses and glaciers. Nearly all the glacier pictures are 

 from the Cornell Glacier which is shown in the large 

 picture, No. i. 



c. A series of views in Greenland showing glaciers and 

 glaciated lands, mounted upon cards and accompanied 

 by explanation, written on the photograph. 



Exhibited by Prof. R. S. Tarr, Cornell University, 

 Ithaca, N. Y. 

 Specimens Illustrating the Occurrence of Mangan- 

 ese IN THE BaTESVILLE ReGION OF ARKANSAS. 



Exhibited by Gilbert van Ingen, Columbia University. 



The manganese occurs in two conditions : i . Original 

 condition as deposited in nodular form in fine mud on 

 the bottom of a deep ocean. 3. Secondary due to re- 

 crystallization after erosion and decomposition of the 

 limestone and shale containing the nodular form. The 

 nodular form occvu's as it was deposited in a shale of 

 deep water oi-igin, which shale rests upon the surface of 

 a limestone of Hudson age, and beneath a limestone of 

 Niagara age. The graduation from the shale with man- 

 ganese nodules to the pure fossiliferous Niagara lime- 

 stone is well shown in the specimens. This nodular 

 form of manganese is not marketable because of its high 

 percentage of contained phosphorus. 



The marketable manganese is the secondary form 

 found in the residual clay which fills cavities formed in the 

 " Hudson" limestone by erosive agencies. It has been 

 formed in the lower portions of the clay pockets by the 

 leaching of the nodules in the shale and limestone and 

 by the subsequent recrystallization, and occurs in masses 

 of irregular shape often weighing several tons. 



