Himanava Mountarys. 209 
Height above the sea 11,529 feet, 
but the highest rocky point of the mountain is 350 feet higher than the 
observatory.. 
As to barometers, we were deficient in those useful auxiliary instruments,, 
those we had, being frequently broken: it is obvious that barometrical deduc- 
tions cannot be put in. competition with geometrical, conducted as the 
following, were :—and that they cannot be used on the great snowy peaks 
which are:not to: be ascended. No barometrical deductions are admitted 
into this paper, except the height of Belville or Sehdranpir above the sea, 
as there:was no other method of determining it: I believe it to be near the 
truth, probably erring in defect rather-than.excess;. I may mention however 
that by co-temporary observations with two barometers by Lieutenant 
Herbert on the Crit, and myself at Sehdranpir, the difference of level 
comes out 11,581 feet, the true or geometrical height being by elevation and 
depression 11,529 feet, a trifling difference, attributable perhaps to chance. 
We made those: barometers out of common.weather. glass tubes and filled 
them ourselves:. We frequently amused ourselves by taking differences of 
level by the: method of observing the boiling point of water as shewn 
by the thermometer; this when common thermometers are used, is of course 
only an approximation, but even with those short and imperfect intruments 
may occasionally be of comparative use. The: results were often surpri- 
singly close, and the greatest error we noted, was once about four hundred 
feet, on a true difference of altitude of 7000: one might expect it to be far 
greater when itis considered what a-small quantity one degree of Farenheit 
is on a thermometer of eight or twelve inches long. I think that Dr. 
