759 
or THE PLUMB-LINE IN INDIA. 
l-897o923 and 1-9030900, 1-4090396 and 1-4259687, 1-1761240 and 1-2041200 
0-8406207 and 0-9030900. The values of d are obtained from the first column in the 
Table of Heights (page 750), or from page 67 of my former Paper. 
The values of ^ S for the three stations, for the various examples of depth, are now 
easily obtained by adding the logarithms of the last columns of the Four Tables of 
Eeduction to the logarithms of S in the Table in page 763, and finding the natural num- 
bers. The results are given for each of the three stations A, B, C, for all four cases of 
depth, m the four next Tables, which 1 call the Four Tables of Deflections in the 
meridian; the totals at the foot of these Four Tables give the final results, viz the 
Deflections under the various suppositions of depth. These I now proceed to discuss. 
§ 0 . Dtscussion of the Deflections under the various cases of depth, and of the effect upon 
the Ellipticity of the Indian Arc. 
13. The Tables thus calculated furnish the following results; 
Deflection in meridian, caused by the mass of 
the Himmalayas and the mountain region 
beyond 
Ditto, by same mass distributed through a depth 
100 miles 
300 miles 
500 miles 
1000 miles 
By subtracting each of the last four lines froi 
results : — 
Deflection in meridian, caused by the mass of 
the Himmalayas and of the mountain region 
beyond 
Ditto, modified by the supposed attenuation of 
matter extending down to a depth of 100 miles 
300 miles 
500 miles 
1000 miles 
At Kaliana. 
At Kalianpur. 
At Damargida. 
27-978 
12-047 
6-790 
26-440 
12-111 
6-856 
21-106 
11-678 
6-866 
17-066 
9-622 
6-670 
11-199 
7-386 
5-220 
m the flrst 
hne, we have the following 
At Kaliana. 
At Kalianpur. 
At Damargida. 
// 
27-978 
12-047 
6-790 
1-538 
-0-064 
-0-065 
6-872 
0-369 
-0-076 
10-912 
2-425 
0-120 
16-779 
4-661 
1-570 
It will be seen how much the Deflections are reduced by this hypothesis, especially 
m the case where the attenuation extends through only 100 miles. In fact, in this case 
the upheaval of the mountains and the consequent attenuation below produce a slight 
deviation the other way at the two further stations. The success of the hypothesis may 
therefore, thus far, be considered to be established, although it remains an hypothesis 
still ; and we must always be in uncertainty, not as to its answering this end, but as to 
