88 MY FIRST JOURNEY IN NORTH-EASTERN TIBET.
about 5 cub.m. in the second. On the right bank grew a little grass and japkak. The only signs of wild creatures were a solitary hare and the tracks of antelopes.
During the course of the day's march we saw hard rock in only two or three places. The first was white quartzite, beside the two small lakes; the second hard crystalline schist, dipping 62° towards the S. 6o° W., beside the little pool. This last jutted up out of the soft ground like a slab set on edge, and possibly belonged to a detached block. At Camp No. XXV, where the stream cuts its way through the hills, there was again hard rock. Amongst the débris in the miry hill there occurred fragments of some sort of pumiceous or scoriaceous rock.
This will be a convenient place to say a word or two about the weather that prevailed during the two days we spent in this locality. From I2 to 2 p. m. on the I oth August it hailed, the clouds coming from the west. The storm signalled its approach by the sky turning blue-black in the west, and a few minutes later the tempest burst. After it was over, the sky cleared a little, but at 4 p. m. it once more darkened, announcing the onset of another tempest, and this proved to be more violent than the other. First came a few harbingers of the storm and gusty squalls, and these were followed by a hard, steady blow accompanied by hail, and last of all a copious fall of snow, the wind slackening off a little. Such is the routine. The tempest was heralded by thunder, which crashed so loudly that the earth trembled, and the lightning flashed incessantly, several times in the mi-
Fig. 70. EROSION TERRACE AT CAMP XXV.
IIIF Color HighRes
