THE SUPPORT OK Til E HIMALAYAS. H3 



on Mr. Lydekker's map, in the position ascribed to the latitude 

 station. The eastern station, Gogipatri, is described as being on 

 one of the long slopes from the Panjal range. Both stations are 

 in the region of the Karewah deposits, south of the newer alluvium 

 of the valley, and the observations gave a deflection of +11" at 

 Poshkar and — 1" at Gogipatri, using the Everest spheroid and a 

 deflection of -f \" at the reference station of Kalianpur ; deflections 

 which become + 15" and + 3" respectively if the Bessel-Clarke 

 spheroid is adopted. 



These southerly deflections were attributed by the Trigonometric- 

 al Survey to the eil'ect of the southerly attraction of the Pir 

 Panjal range, yet it is doubtful whether this cause would, in itself, 

 be sufficient to produce an actual southerly deflection, though it 

 would necessarily reduce the amount of the northerly deflection 

 due to the Himalayas as a whole. An approximate estimate, 

 based on the 32-mile contoured map of India, gives the outward 

 attraction of the mass between the stations and the plains as about 

 + 20" and the inward attraction of the masses towards the main 

 range as about —22", allowing for the Hayford compensation 

 of the visible masses in both cases, the greater proximity of the 

 hills in the former case about counterbalancing the greater mass 

 in the latter, with the result that only a small deflection in 

 either direction is to be expected. 



From this it is evident that the northerly residual of deflec- 

 tion, found at stations up to about 30 miles in from the main 

 boundary further east, has disappeared at these two stations, and 

 this suggests that they lie in the region where the northerly 

 residual, resulting from the defect of compensation in the outer hills, 

 is passing into the region where the excess of compensation in the 

 central part of the range would give rise to southerly residuals. 

 This deduction derives some support from the indications of a 

 general recent uplift of the hills to the north of the valley, but 

 any such inference is rendered unsafe by the fact that the southerly 

 deflection, at; both stations, may be due to the effect of the alluvium 

 filling the depression of the valley of Kashmir, which, as in the 

 case of the Gangctic alluvium, would cause an apparent repulsion, 

 or southerly deflection, of the plumb-line. This cause is, indeed, 

 the only obvious explanation of the great difference in the deflec- 

 tions observed at the two stations, for the Poshkar station is just 

 south of the greatest development of the alluvial deposit, which 



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