I made frequent excursions to the great glacier of Kinchinjhow. Its valley is about four miles long, broad and flat: Chango-khang* [The elevation of this mountain is about 20,560 feet, by the mean of several observations taken from surrounding localities.] rears its blue and white cliffs 4,500 feet above its west flank, and throws down avalanches of stones and snow into the valley. Hot springs* [Supposing the mean temperature of the air at the elevation of the Momay springs to be 26 degrees or 28 degrees, which may be approximately assumed, and that, as some suppose, the heat of thermal springs is due to the internal temperature of the globe; then according to the law of increment of heat in descending (of 1 degree for fifty feet) we should find the temperature of 110 degrees at a depth of 4,100 feet, or at 11,900 feet above the level of the sea. Direct experiment with internal heat has not, however, been carried beyond 2000 feet below the surface, and as the ratio of increment diminishes with the depth, that above assigned to the temperature of 110 degrees is no doubt much too little. The Momay springs more probably owe their temperature to chemical decomposition of sulphurets of metals. I found pyrites in Tibet on the north flank of the mountain Kinchinjhow, in limestones asasociated with shales.] burst from the ground near some granite rocks on its floor, about 16,000 feet above the sea, and only a mile below the glacier, and the water collects in pools: its temperature is 110 degrees, and in places 116 degrees, or 4 degrees hotter than that of the Yeumtong hot-springs, though 4000 feet higher, and of precisely the same character. A _Barbarea_ and some other plants make the neighbourhood of the hot-springs a little oasis, and the large marmot is common, uttering its sharp, chirping squeak.