106 OLDHAM: THE STRUCTURE OF THE HIMALAYAS, ETC. 

 Table 30. — Gravity Stations in the Himalayas. 











Distance from 

 the 



Elevation. 



Bouguer 

 anomaly. 



Hay ford 

 anomaly. 



Station. 



Main 

 Boundary. 



Boundary 

 of hills. 



More 



Simla 

 Kalka 



Mussooree 

 Rajpur 

 Kalsi 



Dehra Dun 

 Fatehpur . 

 Hardwar . 

 Asarori 

 Mohan 



Sandakphu 

 Darjeeling 

 Kurseong . 









110 N. 



10 N. 



1 S. 



3 N. 

 







2 S. 

 S. 

 7 S. 

 9 S. 



14 S. 



20 N. 

 16 N. 



3 N. 



150 



34 

 11 



21 



18 



18 



12 



10 







8 







15,427 



7,043 

 2,202 



6,924 

 3,321 



1,684 

 2,239 

 1,434 



949 

 2,407 

 1,000 



11,706 

 6,966 

 4,915 



— -435 ? 



— 119 



— -085 



— 110 



— 124 



— -098 



— 126 



— -100 



— 114 



— 112 



— -104 



— 150 



— 143 



— 130 



+ -049 

 + -022 



+ -003 

 + 048 



through the three points, from which the correction at intermediate 

 ' stations can be estimated. Either method gives a Hayford anomaly 

 of between -f- *02 and -f- -03 dyne at Darjeeling and of between •()(> and 

 -{- '01 dyne at Kurseong. These results are necessarily approximate, 

 but they are sufficiently near the values which would be derived from 

 detailed computation to show that there is an increase in the force of 

 gravity at Sandakphu, as compared with Kurseong, amounting to a 

 departure of -f -05 dyne from the difference which should result from 

 the hypothesis of compensation adopted in the calculations. 



The northerly residual of deflection at the two latitude stations 

 of Phallut and Tongln, situated about 6 miles on either side of 

 Sandakphu, makes it almost certain that the gradient of increase in 

 the anomaly of gravity will continue to the northwards beyond 

 Sandakphu, and that stations further into the hills would show 

 even higher positive anomalies, though it is impossible to say 

 for what distance this increase would continue. Now a gradient of 

 increase in the excess of gravity of -05 dyne in 30 miles, if continued, 

 would give rise to a deflection of about 9", if the anomaly were pro- 

 duced by a want of adjustment in the compensation. The actual 

 residual deflection being about 10", there is as close aii agreement 



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