_Thecla_ and _Hesperides_ skipped about, and the great _Nymphalidae_
darted around like swallows. The venomous black cobra was common, and
we left the path with great caution, as it is a lazy reptile, and
lies basking in the sun; many beautiful and harmless green snakes,
four feet long, glided amongst the bushes. My dogs caught a "Rageu,"*
["Ragoah," according to Hodgson: but it is not the _Procapra
picticaudata_ of Tibet.] a very remarkable animal, half goat and half
deer; the flesh was good and tender, dark-coloured, and lean.

I remained here till the 15th of August,* [Though 5 degrees further
north, and 5,268 feet above the level of Calcutta, the mean
temperature at Choongtam this month was only 12. degrees cooler than
at Calcutta; forty observations giving 1 degree Fahr. as equal to 690
feet of elevation; whereas in May the mean of twenty-seven
observations gave 1 degree Fahr. as equal to 260 feet, the mean
difference of temperature being then 25 degrees. The mean maximum of
the day was 80 degrees, and was attained at 11 a.m., after which
clouds formed, and the thermometer fell to 66 degrees at sunset, and
56 degrees at night. In my blanket tent the heat rose to upwards of
100 degrees in calm weather. The afternoons were generally squally
and rainy.] arranging my Lachen valley collections previous to
starting for the Lachoong, whence I hoped to reach Tibet again by a
different route, crossing the Donkia pass, and thence exploring the
sources of the Teesta at the Cholamoo lakes.

Whilst here I ascertained the velocity of the currents of the Lachen
and Lachoong rivers. Both were torrents, than which none could be
more rapid, short of becoming cataracts: the rains were at their
height, and the melting of the snows at its maximum. I first measured
several hundred yards along the banks of each river above the