1877.] W. Theobald — Simalayan Olaciation. 137 



must always be less than the external resistance. Putting - for/x, we have 



o 



E = 



which expresses the physical law, namely, that 



Resistance o£ bobbin Diameter of bare wire 



External resistance Diameter of covered wire 



2. RemarTcs on Mr. CamphelVs JPaper on Simalayan Glaciation in 

 the Journal of the Asiatic Society of Bengal, Pt. II, JVo. 1, 1877. By W. 

 Theobald, Geological Survey of India. Communicated hy Mr. H. F. 

 Blanfoed. 



As Mr. Medlicott in his note to Mr. Campbell's paper has termed it 

 a refutation of my views on the ancient moraines of the Kangra district, I 

 would beg to say a few words in arrest of judgment on this point and to 

 show wherein Mr. Campbell has not only failed to controvert my position 

 but even to grasp its cardinal features. 



I do not propose to introduce any new matter in support of my own 

 views but to confine myself to Mr. Campbell's criticism and the more clear 

 explanation of my own position, which I regard as not materially weakened 

 by anything my critic has adduced. 



Mr. Medlicott, it is true, does not go the length that I do as regards 

 the extension of glaciers formerly into the Kangra valley, and it is superflu- 

 ous to admit the weight which such an opinion should carry, but the differ- 

 ence between us is one more of degree than anything else, and if I am not 

 mistaken, Mr. Medlicott differs in an opposite direction no less from Mr. 

 Campbell than from myself. 



On the other hand, Mr. H. F. Blanford in the discussion on Mr. Camp- 

 bell's paper spoke of glacial action so low as 4500 feet, which goes far to 

 bridge over the gulf which separates my estimate of the former limits of 

 glaciers in Kangra from the more restricted estimate currently held on the 

 subject. 



As for whether or no these glaciers protruded into the lower grounds 

 ten miles or so, either beyond or within the general limits assigned to them 

 by me, is, in view of their stupendous development, a matter of little im- 

 portance, and neither under present conditions, either easy to settle or 

 worth contending for, the main question being, did glaciers, during later 

 tertiary times or more recently, descend in Northern India to so low a 

 level as 2000 feet above the sea ? 



Much that I have seen since fully corroborates this view, and it only 

 remains to glance at the arguments which Mr. Campbell has adduced 

 against it. 



