88 NEW YORK STATE MUSEUM 



microscopic analyses, percentage by weight. It is at once apparent 

 that there is a very great range in the ore. The bed sufficiently 

 graphitic to be regarded as ore is something like 25 feet thick, of 

 which one-third appears to be a good workable ore. Crosby had 

 representative samples collected at intervals of 1 foot from two 

 parallel sections 10 feet apart, through the richest part of the bed. 

 He classifies the bed as follows : 



" 1 Eight feet of micaceous quartzite with more or less graphite, 

 chiefly in streaks and affording some graphitic ore. 



" 2 Twelve feet of graphite schist, probably all of workable grade 

 and much of it carrying 10 per cent or more of graphite. 



" 3 Ten feet of quartzite and brown mica schist with some dis- 

 seminated graphite and streaks of graphitic schist. 



"A general or composite grab sample of fifty pieces from the pile 

 of ore from the drift . . . was analyzed by Dr W. T. Hall 

 of the Massachusetts Institute of Technology with the following 

 result: 8.09 per cent of graphitic carbon. This is certainly a very 

 favorable showing . . . and it is equally certain that a con- 

 siderable part of the Johnsburg bed runs over 10 per cent of 

 graphite and some of it over 20 per cent." 1 



Quoted from Professor Crosby's report. 



