128 SCIENCE PROGRESS. 



their energies to inquiries of a purely economic nature. 

 But it is deeply to be regretted that palseontological re- 

 search has not kept pace with stratigraphical, for the work 

 of the survey would be of infinitely more value to other 

 geologists if the fossils collected were always properly com- 

 pared and described. 



When the first edition of the Manual was published, our 

 knowledge was so fragmentary that it was impossible to 

 give a connected account of the geology of India as a 

 whole ; and it was found necessary to break up the book 

 into a series of descriptions of different districts. But so 

 great has been the progress made since that time, that 

 Oldham has been able to adopt a chronological arrange- 

 ment ; and although in many cases the chronology is still 

 very doubtful, this plan greatly facilitates the comprehen- 

 sion of the work. 



In this article it is my object to draw attention to some 

 of the more important of the recent advances in Indian 

 geology. Fuller information on all the points raised will 

 be found in Oldham's Manual, except in the case of one or 

 two observations which have appeared since the publica- 

 tion of that work ; and references to the more important 

 of the papers dealing with the questions discussed are 

 given in the footnotes. 



Few parts of the world can boast a finer development 

 of " gneissic rocks' than Southern India; and no 

 more promising field can be found for their investigation. 

 But unfortunately it was in the early days of the Geological 

 Survey, when petrology was still in its infancy, that this 

 part of India was chiefly studied; and at that time it was 

 almost universally held that gneiss had been formed by 

 the metamorphism of ordinary sedimentary strata. Little 

 attention was paid to these rocks, and on the map accom- 

 panying the first edition of the Manual they were all 

 grouped under one colour. 



Foote was the first to show that it was possible to dis- 

 tinguish a more schistose series, consisting of conglomerates, 

 schists, haematite-beds and lava-flows, from the more truly 



