388 REVIEWS 
home industries, and to discourage useless prospecting. ‘The enormous 
deposits of coal, gypsum, asphalt, salt, oil, gas, shale, limestone, and clay 
are described, and their approximate locations given. Lead, zinc, granite, 
gabbro, porphyry, marble, tripoli, novaculite, and volcanic ash are important 
eposits. Iron and copper are too widely disseminated in the rocks to be 
of value. Gold and silver are not likely to be found. The gypsum and 
asphalt deposits are among the largest in the United States. The granite 
and porphyry are of the finest quality. The introduction of better means of 
transportation will stimulate the mineral industry of Oklahoma. 
C.J He 
Some Problems of the Formation of Coal. By Davip WHITE. Re- 
printed from Economic Journal, Vol. III, No. 4, 1908. 
The author states that typical coal plants grew in greatest profusion 
under a humid and equable, though not necessarily tropical, climate. The 
size and state of preservation of delicate plants is affirmative evidence of 
accumulation in regions of growth. Transported plant remains are char- 
acterized by their macerated condition. 
Anaerobic bacteria are primarily indispensable as an agency in the 
decomposition of organic matter, forming algal, fundamental matter, or 
sapropel. The process which is essentially bio-chemical probably leads 
no further than the formation of peats, humus, sapropelic deposits, etc. 
In the dynamo-chemical stage of coalification the anthracites, bituminous 
coals, and lignites are metamorphosed from peats, lignites, etc. Devolatili- 
zation, the writer believes, is caused not by folding or faulting, but by deep- 
seated horizontal thrust movements. Lithification and partial dehydra- 
tion are attributed to loading pressure: De-oxygenation and de-hydro- 
genation which are essentially chemical results are due rather to bio- 
chemical changes than to dynamic stress. 
In a future paper the writer hopes to show clearly that de-oxygenation 
is a true index of the progress made in the formation of coal and its efficiency 
as a fuel. (Oneida, 
