46 OLDHAM : TOE STRUCTURE OF THE HIMALAYAS, ETC 



factors for a depth of 1137 km., observation at a station 50 miles 

 north of the edge of the hills would show a northerly deflection of 

 4" in excess of that due to calculation, or, in other words, a " residual " 

 | _ 4" if the depth of compensation were 100 miles and a defect, 

 or " residual," of + 4" if the depth were only 50 miles. From 

 this it appears that a variation in the depth to which compensation 

 extends, assuming it to remain similar in character to Mr. Hayford's 

 assumption, would introduce residuals which would be northerly 

 for a greater depth of compensation and southerly for a lesser one. 

 These residuals would not, however, amount to more than three 

 ot four seconds of arc, unless a much greater depth of compensation 

 is assumed than there is any reasonable justification for adopting, 

 and further, the residuals would have their maximum value at 

 the edge of the hills, decreasing in both directions but more slowly 

 towards the interior of the range than beyond its limits. 



Table 8.— Comparison of deflections produced by the Imaginary Range 

 jot Uniform Compensation to depth 1137 km., with those pro- 

 duced by various depths of Centre oj Compensation. 



Compensation 



Depth ok centre of 



Compensation. 







Uniform. 











Station. I 















'j 



'o depth 1137 



45 miles 



35 miles 



25 m 



iles 



i 



km. 



Defl. Diff. 



Defl. 



Diff. 



Defl. 



Diff. 



— 10 



— 11 



| 

 — 14 — 3 



— 12 



_, ! - , 



+ 2 



— • 9 



— 13 



— 17 —4 



— 14 



-i -ii 



+ 2 



8 



— 15 



— 19 —4 



— 10 



— i 



— 13 



+ 2 



_ 7 

 1 



— 16 



— 21 —5 



— 18 



— 2 



— 14 



+ 2 



— 6 



— 17 



— 22 — 5 



— 19 



— 2 



— 15 



+ 2 



— 5 



— 18 



— 23 —5 



— 20 



— 2 



— 15 



+ 3 



4 



— 19 



— 24 — 5 



— 21 



— 2 



— 16 



+ 3 



— 3 



— 20 



— 26 — 6 



— 22 



— 2 



— 17 



+ 3 



— 2 



— 21 



— 27 —6 



— 23 



— 2 



— 18 



+ 3 



1 



— 24 



— 31 —7 



— 27 



— 3 



— 22 



+ 2 







— 53 



— 61 —8 



— 57 



— 4 



— 52 



+ 1 



+ 1 

 + 2 

 + 3 



+ 4 

 + 5 



— 15 



— 20 —5 



— 17 



— 2 



— 13 



+ 2 



— 9 



— 12 —3 



— 9 







— 7 



+ 2 



— 5 



— 7 —2 



— 5 







— 3 



+ 2 



— 3 



— 4 —1 



— 3 







— 2 



+ 1 



— 2 



— 3 —1 



— 2 







— 1 



+ 1 



i 



+ 6 



— 1 



— 2 —1 



— 1 







— 1 







+ 7 

 + « 

 -t- 9 







— 1 —1 























— 1 











































+ 10 







[0 



















[ 194 ] 



