504 



NATURE 



[January 15, 1920 



though it has not yet been proved that this boulder 

 bed is not the equivalent in age of the Carbonifer- 

 ous Talchers. The Simla and Jaunsar slates, the 

 Dalings of Sikkim, and the Shiliong quartzites in 

 Assam are all correlated with the Dharwars of 

 Southern India, and, probable as these correla- 

 tions may be, even as regards lithological re- 

 semblance there is little in common between these 

 formations and the highly altered schists and 

 jaspers of the typical Dharwars. Again, in the 

 table giving the Cambrian succession of the Punjab 

 Salt Range, the salt marl is placed at the base of 

 that system, though it has recently been shown 

 that there is good reason to believe this peculiar 

 formation to be of Tertiary age. 



Dharwars, which would make them the oldest 

 rocks of the Peninsula (p. 6g). Insistence is laid 

 (pp. 135, 150) upon the importance of the strati- 

 graphical break at the close of the Carboniferous 

 period, which separates the Dravidian and Aryan 

 groups of Sir T. Holland's classification of the 

 Indian geological sequence. Full attention is also 

 given to the recent discovery in Kashmir of beds 

 containing the characteristic flora of the Talcher 

 series, associated with marine strata, thus fixing 

 a base limit for the Gondwana system, and closing 

 a long-standing controversy. 



A useful chapter on " Economic Geology " 

 closes this part of the work, and then follows a 

 special chapter on the geology of Kashmir, where. 



Fig. 



-" Marble Rocks" (Dolomite marble), Jalalpur. From " Geology of In Jia for Sludeiits, 



The arrangement of the book follows the usual 

 lines. The physical features, mountains, glaciers, 

 etc., are each briefly dealt with in the opening 

 chapter. (Some of these are again described in 

 a chapter on " Physiography " towards the end 

 of the book (chap, xxv.), a somewhat peculiar 

 arrangement, resulting in a good deal of repeti- 

 tion.) Then follow the various systems from 

 Archaean to Pleistocene and Recent, the informa- 

 tion with regard to each being carefully and 

 clearly given in sufficient detail. Full advantage 

 is taken of recent advances in our knowledge of 

 Indian geology. Allusion is made to the revolu- 

 tionary ideas of Dr. Smeeth and his band of 

 workers in Mysore concerning the age of the 



NO. 2620, VOL. 104I 



as the author remarks, "within a small geo- 

 graphical compass one of the finest developments- 

 of the stratified record seen in the Indian region 

 and perhaps in the world " is revealed, in a situa- 

 tion more accessible to the student than any other 

 in the whole length of the Himalaya. It may 

 here be remarked that much remains to be done 

 before the geology of this fascinating country is 

 worked out in detail. 



The book is written in clear and good English, 

 and is well got up. Very few typographical errors 

 have been noticed, but among them may be men- 

 tioned "Jena," presumably for "Jura" of Spitt 

 (p. 165); "corrosion" for "corrasion " (p. 277); 

 and twice (pp. 198, 200) " Physa princepii " for the 



