40 
The Trigonometrical Survey of India. 
[No. 1, 
Height 
above sea 
level. 
Haines of Stations. 
/• 
Denominator 
of 
vulgar frac¬ 
tion. 
412 
Toolsipoor, T. S. 
.0763 
13.1058 
478 
Anarkali, T. S. 
.0744 
13.4432 
7732 
Jagesar, H. S. 
.0463 
21.5983 
6994 
Birond, H. S. 
.0652 
15.3374 
10101 
Khankra, H. S. 
.0579 
17.2652 . 
8526 
Soonehalia, H. S. 
.0624 
16.0256 
6946 
Ghoongti, II. S. 
.0652 
15.3374 
7079 
Ranigarli, H. S. 
.0687 
14.5624 
5675 
Mabegarh, II. S. 
.0750 
13.3333 
7371 
Ghandial, H. S. 
.0698 
14.3266 
12541 
Kiderkanta, H. S. 
.0480 
20.8377 
9946 
Nagtiba, H. S. 
.0521 
19.1902 
2970 
Dhoiwala, H. S. 
.0628 
15.9363 
7454 
Banog, H. S. 
.0612 
16.3479 
3161 
Arasot, II. S. 
.0565 
17.6897 
11997 
Chur, H. S. 
.0530 
18.8857 
78. Conclusion deduced from foregoing table .—Now since 
Sin incidence 
-= 1 -f m in the mean state of atmosphere and at 
Sin refraction 
the level of the sea, and also, since the quantity m varies with the den¬ 
sity of the atmosphere, so that when the density of the air is only the 
n tli part of what it is at the level of the sea, the refractive power is 
on 
there only 1 4-, it might have been expected from these tabulated 
n 
1 
results that in the first instance, fa - : -— : - ; - : - : — 
height of station of observation. 
No such law, however, is to he found unless the numerous exceptional 
cases he excluded to make a rule. 
74. Wherefore it appears, that the law of variation injfdue to 
variation in the density of the atmosphere, consequent on variation 
in height, is completely absorbed and lost sight of in the irregular 
variations, arising from local causes and also from the unavoidable 
imperfections of observation to points so ill-defined as the apices of 
snowy mountains. 
75. Finally it is to be noticed that the foregoing method is 
acknowledged to be imperfect and unsatisfactory, but compared with 
the ordinary mode of finding f from reciprocal vertical observations, 
