136 Miscellaneous Bibliography. 
By the aid of this subterranean geological map, it is easy to determine 
the strata which would be struck at any given point in the vicinity of 
Paris; for the colors indicate the formation lying immediately under the 
diluvium, and, as the point selected will fall between two horizon 
curves representing the surfaces of the different strata, a fourth propor- 
tional is all that is required to calculate the depth at which any one of 
these surfaces may be reached. 
The method employed in the execution of the map facilitates, more- 
ad 
tageously used in exploring for deposits of economic value. The chart 
has other features of interest which will repay examination. It is prob- 
ably the most elaborate geological map ever constructed, and will doubt- 
less long be regarded as a model. 0. C. M. 
2. The American Naturalist, a Popular Magazine of Natural His- 
tory.— Under this title, the Officers of the Essex Institute, Salem, Mass., 
propose to publish a monthly magazine, commencing early in the present 
ea 
e object of this journal is to supply a long-existing demand for a 
popular illustrated magazine of Natural History, devoted to the exposi- 
tion of scientific topics in a free and familiar manner, without those 
technicalities which often render the mass of such reading tedious and 
difficult. 
editors are A.S. Packard, Jr., M.D., in connection with E. S. 
Morse, Alpheus Hyatt and F. W. Putnam. = 
3. A Manual of Blowpipe Analysis and Determinative Mineralogy ; 
by Witutam Evpernorsr, M.D. Third edition, 12mo, pp. 179, revised and 
greatly enlarged. Philadelphia, 1866. (T. Ellwood Zell.) —The value of 
this useful manual on blowpipe analysis has already been ized 10 
oe ge noticing eek second edition. But we have failed to discover 
evidence € revision enlargement 
the third edition. 
on the title page of 
ae 
