Geology and Natural History. 385 
of the “Spring Valley Gravel Mining Claim,” Cherokee, Butte 
county, California. A microscopic examination shows these sands 
for the removal of any carbonates which might be present. There 
was no effervescence from this treatment. The same sample was 
then digested in strong sulphuric acid of a high temperature to de- 
osmium and ruthenium. His paper will be found in the American 
i for 
ume. No doubt, some diamonds are und, ] 
by hard knocks to powder.”—Engineering and Mining Journal, 
Feb. 25, 1873. 
