^elation to the Constitution of the Earth 3 s Crust. 27 



Heights. 



Station. 



Local 



attraction 



relative to 



Punnee. 



ft. 



1914 

 1946 

 1714 

 1120 

 1693 

 1763 

 1641 



Mean 1685 



Kodangal 



+i-oo 



-079 

 +0-93 

 +032 

 +0-79 

 + 1-75 

 -042 



Damargida 



Somtana 



Badgaon 



Ahmadpur 



Kalianpur 



Pabargarh 





+0-42 





These numbers will be uniformly increased or diminished 

 by any local attraction there may be at Punnse, which is not 

 situated on an infinite plain, but where proximity to the coast 

 places it under conditions different from those at the stations 

 which we are referring to it. 



To appreciate what these differences from zero attraction at 

 the stations imply, we observe that one vibration per diem due 

 to local attraction corresponds to about 645 feet of elevation 

 of a plain ; and therefore, since the root (supposed of density p) 

 displaces a layer of density <r, one vibration in defect caused 



by it wall correspond to — — x 645, or 6172 feet, i. e* to 

 1-1707 mile of root. a ~P 



We see, then, that the root at Damargida, where the attrac- 

 tion is —0*79, would be about 0*92 mile too deep for local equi- 

 librium ; and at Kalianpur, where it is +1*75, it would be 

 2-046 miles too shallow — these estimates being of course subject 

 to the uncertainty belonging to local attraction at Punnse. 



If we assume the crust at Punnse to be 25 miles thick 

 (which I have shown in my ' Physics &c/ to be probable for 

 places on the sea-coast), then, the depth for zero attraction of 

 the root at Damargida being 3*527 miles, the actual depth there 

 would be 5*171 and the whole thickness of the crust 30 miles. 

 At Kalianpur, the depth for zero attraction being 3-195 miles, 

 the actual depth would" be 1*149 and the whole thickness 

 26 miles. These two instances are the greatest variations 

 that occur throughout 8 degrees of latitude, and there are 

 but two others of similar amount among the sixteen stations 

 between Kaliana and Punnse. 



Although these varying local attractions at the several 

 stations make it clear that this region is not in hydrostatic 

 equilibrium everywhere locally, nevertheless, the relative 

 attractions being at some stations positive and at others 

 negative, it is quite possible that it may be as a whole sup- 



