Letter from the Himmalaya. 
49 
1830 .] 
stead of laughing at me, he seemed to take it gravely. I have since repeated the fact. 
We accounted for the natives with us not being honored with a sight, from the cir- 
cumstance of their want of new light to see the same. The measures we took of 
t?ie peaks St. George, &c. must, not be considered as decisive of the heights of the 
Himmalaya: those measures were not taken under favorable circumstances either in 
the barometrical or geometrical parts of the operations, but I judge that the error 
does not exceed 200feet on the whole. The question of the heights of the snowy peaks 
is determined from a very extensive trigonometrical operation proceeding, instituted 
for the purpose, and carried on with excellent instruments, much care and labour, 
and upon just principles. An account of these operations will be published in all 
its detail for the satisfaction of the scientific. The height of some of the peaks in 
this survey is about 23000 feet above the level of the sea, but there is one in the Ca- 
raaun survey, upwards of 25000, which is, as far as we know, the highest mountain 
on the earth. People in Europe are unwilling to believe that the Himmalaya are higher 
than the Andes, but the examination of our data will satisfy them that every precaution 
has been taken to confine the effects of terrestrial refraction within very narrow li- 
mits, by modes which it would take up too much room to describe here, but the 
chief principles of which are to take reciprocal observations of elevation and de- 
pression, and so to dispose the terrestrial arcs that they may be only of a moderate 
extent, and the angles of apparent elevation as large as possible. We find that at low 
elevations, as 1°40' and 2°, and at distances of 40 to 60 miles, mountains of from 6500 
to 12000 feet are subject to be affected by refraction in the ratio of nearly T * 3 of the 
subtended arc. In only one instance, and that on a long arc (Karndl and the Chur 
peak) and in dark weather too, it was so great as£. Within the mountains, where the 
air is light, clear and drier, it is T * 5 and a small quantity where the arcs are only 
of 15 or 20 miles and the angles of elevation 5°, 8° and often more degrees. You 
are to understand by this that the arcs are expressed in feet and turned into arcs 
of oblique circles ; but, for the sake of explanation, we may roughly consider as geo- 
graphical miles the distances from station to station, and take a large ratio of re- 
fraction as i^th. Thus, if a peak at the distance of 120 such miles appears elevated 
above the horizon 2°. or 120', its apparent elevation is to be reduced 12', its true 
angle then is 1°. 48'; and 12' being a large proportion when the quantity of refrac- 
tion is only assumed, it is not satisfactory to rely on such long arcs and small 
angles of elevation of objects seen through a moist and dense medium, as is the at- 
mosphere of the plains. But they are of great use in comparing the heights deter- 
mined on the whole arc, with the sums of those given by smaller arcs and greater 
angles of elevation ; and the comparison proves, that even giving to calcula- 
tions made hitherto, often on long arcs, an extreme quantity of refraction the 
peaks of the Himmalaya surpass the heights of the loftiest of the Andes by some 
thousands of feet, which that prince of travellers and excellent observer, M. F- 
Humboldt, will prove if be comes, and I wish he were here to do so. His researches 
also will throw great light on the geology of our mountains, and their vegetable and 
mineral productions, and other subjects beyond our skill : but as to the measure- 
ments of their distances, their latitudes, longitudes, and heights, I think he will fully 
confirm what we have done. Perhaps in England they think that officers of the army 
are unequalto the task, but really it is not mysterious ; good instruments, time, care 
perseverance, and a moderate skill in calculation, are all that is required. We have 
followed the methods of those skilful observers, Roy, Mudge, Dalby, and Lambton 
in the English surveys, and those of Delambre and Le Gendre in the French, in 
calculation, principally the latter, as their calculations are the most ready : but they 
all give the same results. In the observations themselves, w'e adhere to the English 
practice, which is adapted to our instruments. Excellent as the French repeating 
circles no doubt are, and easy to transport, their construction requires several cor- 
rections and calculations, which take up time, and may lead the unwary and less 
skilled into mistakes when much is to be done ; but the English circles, by Trough- 
ton, which give, when well adjusted, direct angles, horizontal and vertical, are, though 
less portable, more direct and downright in use. We returned to Gangotri °of 
course, by the same route, and as all things are more or less wild by comparison 
that edgeway, and by us once considered remote place, seemed like a welcome home! 
We found our people all well, but rather hungry. Thence we went by Bhairoghatie 
and Derail to Stiki. Having now no object in view, except to return, the ways 
seemed rougher, and we were more fatigued. We arrived at Sfiki on the 6th 0 f 
June, when the rains began in earnest ; it rained night and day till the 13th, with a 
degree of violence I never before witnessed, and our situation was very unpleasant 
having no other shelter than our very little tents, smaller than those used by the 
