284 REVIEWS 
history, and a brief statement of geologic and economic conditions of 
each. It forms an invaluable book of reference for everyone interested 
in the copper industry. The data are brought up to July, rort. 
aN 1B), 155, 
The Relation of Bornite and Chalcocite in the Copper Ores of the 
Virgilina District of North Carolina and Virginia. By 
FRANCIS BAKER LANEY. Proc. U.S. National Museum, XL. 
Washington) tort. Pp..522_24) pls. 102.00; 
After a brief discussion of the geology of the region the author 
describes sections of the ores from a microscopic study. None of the 
bornite appears to be secondary. The chalcocite occurs as secondary 
veinlets in the bornite, and as intergrowths with bornite showing that 
in the latter case the two minerals formed simultaneously. The author 
confirms Graton’s view that the chalcocite is primary, and the evidence 
is convincing. If, however, the ore deposits are older than the metamor- 
phism, the same result could arise from the recrystallization of a second- 
ary ore. This possibility has not been discussed but is suggested by the 
work of Emmons in Maine and in the Ducktown region. 
XD) 183. 
Iron Mines and Mining in New Jersey. By W.S. BAYLEY. Geo- 
logical Survey of New Jersey, Vol. VIII, 1910. Pp. 512; 
pIssi2s maps ities. 20: 
The report gives a brief history of iron mining in New Jersey since 
its initiation in 1685. A brief outline of the geology of New Jersey 
pertinent to the subject follows, and the remainder of the report deals 
with the iron ores themselves. These are of four types, bog ore, limo- 
nite, red hematite, and magnetite. In early years considerable bog 
ore was utilized. Later, the limonites became of importance. At 
present, the magnetites are mined almost exclusively. The ores are 
described separately, as to their appearance, chemical composition, 
manner of occurrence, origin, and production. Much space is given 
to the description and history of individual mines. H.C: 
The Mineral Production of Virginia during 1909 and 1910, Biennial 
Report on. Virginia Geological Survey Bulletin No. 6. Pp.123. 
The mineral production for t909 and 1910 is summarized, and com- 
pared with that for several previous years. Iron, coal, and clay are of 
major importance. The production of most of the substances mined 
