Geology. 381 



ments retained, a few have been omitted, and about forty new 

 experiments have been incorporated. In addition to the tables 

 of natural functions, which are common to both editions, 18 

 tables of physical and mathematical constants have been placed 

 near the end of the new volume. As a consequence of all these 

 mutations the manual has expanded from 294 to 417 pages. If 

 possible, the quality of the book has kept pace with its increase 

 in scope. h. s. u. 



13. Die Bearbeitung des Glases auf clem Blasetische; by D. 

 Djakonow and W. Lekmantoff. 2d edition. Pp. xv, 196, 

 with 34 text-figures. Berlin, 1911 (R. Friedlander & Sohn). — 

 The real author of this manual is Lermantoff, since he had as a 

 nucleus for the first edition, which appeared in 1895, only a few 

 fragmentary notes left by Djakonow, who died in 1888. Ler- 

 mantoff has taken great pains to supplement his own knowledge 

 of the art by consulting with three of the best professional glass- 

 blowers of St. Petersburg. Consequently the book is character- 

 ized by giving the most minute details as to how to proceed in 

 any given case. Undoubtedly it is very reliable and up to date. 

 On the other hand, the volume is not well-balanced because pages 

 128 to 155 are devoted to the making of mercury-in-glass ther- 

 mometers, while pages 155 to 195 deal with the calibration of 

 such thermometers, a theme which pertains to laboratory manuals 

 but not to a practical guide to glass-blowing. h. s. it. 



II. Geology. 



1. West Virginia Geological Survey: Wirt, Roane, and 

 Calhoun Counties ; by Ray V. IIennen, Assistant Geologist. 

 1911. 573 pp., 3 maps, 15 plates, 6 figures. — In common with 

 the previously issued West Virginia Reports, the description of 

 Calhoun, Roane and Wirt counties is prepared in such a manner 

 as to be directly useful to those interested in petroleum, gas and 

 coal, and agriculture. The value of soil is particularly empha- 

 sized by the State Geologist and attention is called to the damage 

 resulting from deforestation. A chapter on the Historical and 

 Industrial Development of the area, and a meagre discussion of 

 the Physiography is followed by a detailed study of the Geolog}% 

 including chapters on General Geology, the Dunkard Series, the 

 Monongahela Series, the Conemaugh Series. An unusually large 

 list of carefully measured sections is given. An examination of 

 the geologic structure shows the area to be located on the eastern 

 flank of the Great Appalachian geosyncline, which in this area is 

 modified by minor folds, embracing six anticlines and five syn- 

 clines. The care with which structure contours have been worked 

 out and recorded on the map is justified by the fact that structure 

 is the primary control in the distribution of oil and gas, — the 

 chief mineral wealth of this group of counties. The results of 



