304 Scientific Intelligence, 
narrow gauge railways, mining law, the geographical distribution 
i 
of metals and ores, the origin of gold dust and gold nuggets, 
etc., etc. 
Incidentally to the descriptions of mining districts, a very con- 
siderable amount of information respecting the topography and 
the geology is given. This is true especially of the chapters upon 
the Territory of Arizona, which was visited by Dr. Raymond's 
assistant, Mr. Tilers. We find, for example, p. 230, the best de 
scription of the nature and extent of the great basaltic bed along 
the Gila river that has yet been given. 
In the five chapters devoted to metallurgical processes, there is 
one upon the treatment of auriferous ores in C ich in- 
cludes a description in detail of the stamp batteries, and the 
arrangements for concentration. It is thorough and scientific, and 
is a valuable contribution to the literature of the mechanical treat- 
the product of stamps. The cost of gold extraction at steam 
mills is deduced as $3.74 per ton, including the interest on capital 
and the loss of quicksilver. Mr. Hague, in the volume upon Mir 
ing Industry, p. 555, makes the cost, exclusive of interest on cap 
ital, $3.69 per ton. 
produced $25,000,000, and Nevada $16,000,000, Of quicksilver, 
the production was 29,546 flasks, being about 4000 flasks less than 
in 1869, and the price had advanced from 60 to 90 cents. 
e volume, throughout, gives evidence of great labor and 
care in its preparation, and is a most acceptable addition to ow 
knowledge of the mineral resources of the western portion of the 
co 
2f Geology of Oxford and the Valley of the Thames ; by Joux 
Puiturrs, M.A., F.R.S., etc., Prof. Geol. in the University of Ox- 
Britain, has done a great service to general Bass! in the pre 
paration of this work on Oxford geolog e 
as old as any in Scotland—and the representatives, therefore, 
on. e ee. 75 
part of the volume is taken up with the lias and odlite, and in t 
