relation to the Constitution of the Earth' *s Crust, 3 



that of the height ; and when these together had been allowed 

 for, the corrected vibration-number so determined was re- 

 garded as the vibration-number for that station reduced to 

 the sea-level. Had these disturbing circumstances been cor- 

 rectly estimated, and had no others of a hidden kind existed, 

 this vibration -number ought to have tallied exactly with that 

 belonging to the latitude of the station. It turned out, how- 

 ever, that they were usually different, and for the most part 

 in defect, often to a considerable extent. " There appears to 

 be no escape from the conclusion that there is a more or less 

 marked negative variation of gravity over the whole of the 

 Indian continent, and that the magnitude of this variation 

 is somehow connected with the height. Let us group the 

 stations as follows, omitting Ismailia and Kew as foreign.'''* 



" I. Coast and Island Stations. 



Station. 



Height 

 in feet. 



Apparent varia- 

 tion in vibration- 

 numbers. 



Punnae 



48 



-168 



6 



6 



5 



-2-65 

 -2-56 

 +1-37 

 -1-21 

 -0-31 

 -3-24 

 -3-39 

 -1-81 

 +0-75 

 -1-27 



Kudankolaru . . . 

 Minicoy 







Mangalore 



Madras 



Cocanada 



Colaba 



7 

 27 



9 

 35 



Calcutta , 



18 



Mean ... 



33 



-1-43 



" II. Inland Stations less than 1000 feet high. 



Station. 



Height. 



Apparent varia- 

 tion in vibration- 

 numbers. 



Mallapatti 



Pachapaliam . . . 



288 

 971 

 810 

 717 

 810 

 879 

 706 



-3-77 

 -441 

 -3-60 

 -4-30 

 -6-14 

 -6-88 

 -601 







Uoili 



Meean Meer ... 

 Mean ... 



740 -5-02 



Loc. cit. p. [142]. 

 B2 



