1894- SOME NEW BOOKS. 457 



able books of reference, and as models of what this sort of work 

 should be. The fact that they have been out of print for some years 

 showed how well they did what they were planned to do. Great 

 progress has meanwhile been made in the geological survey of 

 India, and a new edition, brought thoroughly up-to-date, was there- 

 fore much to be desired. The preparation of this was entrusted to 

 Mr. R. D. Oldham ; his " Bibliography of Indian Geology " (1888) 

 suggested him as the most suitable man for the task, since a thorough 

 acquaintance with the literature of the subject was one of the most 

 essential qualifications. Mr. Oldham, moreover, has shown in 

 numerous contributions to the Recoyds and Memoivs of the Indian 

 Survey, and in his recent sketch of " The Evolution of Indian 

 Geography" in the Geographical Jonvnal (March, 1894), that he is 

 thoroughly in sympathy with the enquiries regarding the past 

 physical geography of the country. And consideration of these is 

 probably the only method of compiling a work that shall be 

 interesting to read as well as valuable for reference. 



In comparison with the former edition, the present has many 

 advantages ; it is issued as one volume instead of two ; the scale of 

 the map is reduced by about a third, and is, therefore, handier of 

 reference, though there is more information in it ; the long glossary 

 is omitted ; a most useful novelty is introduced in the index of 

 localities, which occupies 32 pages ; the latitude and longitude of 

 each place is given, so that those unacquainted with the details of 

 Indian topography can follow the descriptions with ease. The greatest 

 improvement, however, is the abandonment of the system of describing 

 the country in provinces ; this method of treatment was no doubt 

 inevitable in 1879, when the correlation of the rocks in the different 

 regions was much less advanced than at present. The fact that 

 description by formations instead of by provinces is now possible is 

 one of the principal measures of the progress effected, which this 

 volume attests. It is owing to this change that the work has been 

 rendered more compact, for there is now one story instead of many. 



In the list of contents Mr. Oldham has adopted the useful plan 

 of printing in heavy type the titles of all those paragraphs which are 

 either quite new or have been almost entirely rewritten. This, besides 

 showing how much is to be credited to the original authors, directs 

 attention to the subjects on which most work has been done in the 

 interval between the two editions. Thus we see at once that little has 

 been added to our knowledge of the pre-Palaeozoic, the Palaeozoic, 

 the marine Jurassic, and the Cretaceous rocks of the Peninsula, or of 

 the Deccan Traps. We note the absence of fresh information on the 

 last of these with regret, for though Dr. Blanford's sketch of the 

 subject (chap, xi.) is an admirable one, there are many points in the 

 detailed stratigraphy, and especially in the petrography, on which 

 further information is most desirable. In fact, in most of the 

 Peninsular area, the facts remain much as they were, the principal 

 additions being made to the knowledge of the correlation of the 

 rocks with other areas in Asia, Africa, and Australia. Thus the 

 description of the stratigraphy of the Gondwana system remains 

 practically the same as before, though the chapter on the 

 homotaxis of this formation is almost wholly new or rewritten. 

 The fact that the great controversy as to the true correlation of 

 this system is now at an end is noted with relief. 



The principal changes in the volume are in chapters viii., xviii., 

 and xix., which are entirely rewritten or new. The first is the one 



