142 
These metalliferous ranges extend southwards through 
Arizona and New Mexico into the great Mexican mining 
districts, and northwards to an unknown limit. The 
principal obstacles to their wealth being realised are, 1. The 
hostility of the Indians, 2. The want of wood, 8. The diffi- 
culties of carriage. These however are swiftly being 
removed. The Indians are rapidly perishing, and the rail- 
ways are bringing places hitherto inaccessible within reach 
of the seaboard and the Eastern States. And although the 
lonely plains covered with sage-brush which sweep round 
the metalliferous ranges almost like a sea, and at a height of 
from 4000 to 5000 feet, are without a tree, the Sierra 
Nevada on the one hand, and the Rocky Mountains on the 
other, offer an endless supply of timber. It seems therefore 
that the production of silver in this district is likely to be 
largely increased. Unless the demand keep pace with the 
supply, the price must necessarily fall. F ourteen tons of silver 
coined at the San Francisco mint were sent to the Eastern 
States on 21st of March last, and the export from San Francisco 
to China, which was under one million sterling in 1874 
according to Sir Hector Hay, in 1875 reached one and a 
half millions, which gives an increase of 50 per cent, and 
this in spite of the extraordinary depression of trade. 
On some Isomerides of Alizarine,” by Edward Schunck, 
Ph.D., F.R.S., and Hermann Roemer, Ph.I). 
Considering the importance of everything connected 
with the history of alizarine, we have been induced to 
undertake the study of such of the isomerides of that body 
as we have been able to obtain. These isomerides are 
interesting from a theoretical point of view, as presenting a 
problem with regard to internal constitution which has 
not yet been solved, and technically some of them are 
interesting as they occur along with artificial alizarine and 
not being available for tinctorial purposes are the source 
