400 Miscellanies. 



of the last number, (for Oct. 1835,) of that valuable work, " The 

 American Journal of Science and Arts, conducted by Professor 

 Silliman, of Yale College, Connecticut.''^ The extent of the re- 

 gion described comprises about five degrees of latitude, and as many 

 in longitude, on each side of the river Ohio. The mineral treasures 

 are precisely those v^^hich are most available to the comfort and pros- 

 perity of an industrious and enterprising people: rock salt, or rather 

 brine springs, containing 15 per cent, of salt ; coal in numerous 

 beds, some many yards in thickness, and of an excellent quality ; 

 ironstone, of various qualities ;lead ore, limestone, and millstone, 

 &c. The coal of this vast region occurs in regular strata, scarcely 

 troubled by the faults and dislocations which so much impede mining 

 operations in other districts. In general the strata have very little 

 inclination, and present great facilities for working. The salt springs 

 are bored for, in many situations, to the depth of 600 feet, and even 

 900 feet. When the bed which contains the salt water is first pier- 

 ced, there is generally a great rush of carburetted hydrogen gas 

 emitted : it has, in some instances, been so violent as to blow up the 

 boring rods. The memoir is accompanied by explanatory sections, 

 which presents at one view the thickness and succession of the 

 strata, and is, in every point, deserving of the attention of the ge- 

 ologist, and of all who feel an interest in studying the resources and 

 future prospects of the western United States. The memoir occu- 

 pies 154 pages, and is accompanied by 36 plates, besides a large 

 map of the region." 



Dr. Hildreth's memoir is highly commended in the London and 

 Edinburgh Philosophical Magazine, and an abstract is given of its 

 contents. 



Dr. J. L. Comstock, M. D., has published a second edition of his 

 "Outlines of Geology, &;c. designed for the use of schools and gen- 

 eral readers." The work is enlarged, particularly in facts relating 

 to American Geology, and it is furnished with new illustrations, by 

 wood cuts. 



