368 
CHEMICAL ANALYSES OF ROCKS. 
For convenient reference the analyses of rocks made for 
this report are tabulated below. Of these analyses, numbers 
.3.25,975195.141,,16,:17,,18,2195°20,° 21122 223 04 27002 
28, 29 have been made by Dr. Car. Winter; numbers 2, 4, 10, 
15, 27, by Mr. С. Dertersen; numbers 12 and 14 by Mr. Car. 
CHRISTENSEN; and numbers 6, 8, 13 by the author. The same 
analyses, calculated at 100 per cent. omitting water, are given 
under the numbers la—29a. For the calculated mean compo- 
sitions of the agpaitic main types the reader is referred to the 
table (p. 344). 
