GEOLOGY OF CENTRAL INDIA. 59 



the clouds and mists gathering on the mountains here, .exhibit them 

 of a dark and sombre hue, and there, spots of green may be observed 

 glittering in all the brightness of reflected sunshine. These causes not 

 only modify the external appearance of the country, but even the shape 

 of the moimtams seems to undergo a change. 



With regard to the Rocks of this District, they are all probably 

 based on granite. — Of this, however, I can offer no proof, except such as 

 are derived from analogy, and many of the granites appear so intimately 

 connected with the other rocks, that it is impossible prima facie, to say 

 which ought to be considered the eldest and which not — a gradual 

 passage of the granites into rocks, resembling the greenstones of the 

 trap formation may, in many situations, be observed in this district. 

 Dr. MuccuLLOCH has described similar appearances in Scotland, and 

 has drawn from the circumstance conclusions, the correctness of which 

 I cannot take upon myself either to contradict or support. — I may be 

 permitted, however, to remark, that conclusions drawn from the external 

 characters of rocks, appear to me liable to considerable objections. 

 These may be modified by many circumstances. Neither can I believe 

 that the circumstance of one rock occurring stratified and another unstra- 

 tified, justifies us in concluding that these two rocks have owed their 

 formation to different causes. In this district we often observe a rock 

 in one situation stratified, and at a little distance from it another of an 

 exactly similar nature, in other respects, unstratified. An instance of 

 this kind I have particularly remarked at Phulana, about twelve miles 

 north of Merta, where there occurs a series of alternations of a close 

 grained grey granite, with hornblende rock approaching to primitive 

 greenstone. — Some of the alternating beds appear distinctly stratified, 

 while others resemble an unstratified mass, of a prismatic form, inter- 

 posed among the other strata. It is impossible to distinguish which is 



