On August 12 I rode with Rabsang and a Tibetan up to the foot of Gurla Mandatta. We crossed the great highway between Tugu-gompa and Purang. A wolf took to flight; occasionally a hare leapt up out of the steppe grass, and locusts flew about noisily. We rode into the mouth of the Namreldi valley, a resort of robbers, and its crystal stream, between walls of solid rock, carried 101 cubic feet of water, as compared to the 37.8 cubic feet at the place where it enters the lake. The rest of the water, therefore, pours into the lake under the detritus. A few miles farther west we halted at the mouth of the Selung-urdu valley, which has a glacier in its upper part. At half-past nine o’clock the bed was dry, but at half-past one a river with rapids and waterfalls poured down a volume of 63.9 cubic feet of exceedingly muddy water, which reached the lake in the subterranean springs. The view from this elevated spot is magnificent. We have a bird’s-eye view of Tso-mavang, and in the west gleams the bright blue Langak-tso. The survey we can here take of the country is very instructive. The denudation cones of Gurla Mandatta, consisting of sand, rubbish, and boulders, extend northwards like inverted spoons; their extremities dip under the surface of the lake, and cause the fluctuating depths sounded on lines 1 and 2. From camp 218 Robert executed a line of soundings at right angles to the bank down to a depth of 190 feet.
Every day with its observations brought me nearer to the solution of the problem I had proposed to myself. As we rode northwards on the 13th along the western shore we dug wells at some places 10 yards from the bank. The ground consisted of alternate layers of sand and clay: on the top, sand; then a layer of decaying vegetable remains; then a foot and a half of sand which rested on clay. A pit 2 feet deep slowly filled with water up to the same level as the surface of the lake. The water permeates the sand and rests on the clay. If this layer of clay stretches, as seems likely, across the narrow isthmus to the shore of Langak-tso, it is evident that the water of Tso-mavang filters through the beds of sand and pebbles to the western lake. I was already convinced that even now when the old canal has ceased to act, an underground connection must exist between the two lakes. But the fact that the water of Tso-mavang is quite sweet is no proof that the lake has an outlet, seeing that it is only a few years since the canal was silted up.
Again we encamped below the hospitable monastery Gossul. On August 15 I rode with Rabsang and a Tibetan across the hilly isthmus between the two lakes in order to get a look at the country on this side also. We ascended sharply to the highest point of the ridge, where there is a fine view over Langak-tso with its picturesque rocky shores and projecting points and capes, its bays and islands, and its frame of steep mountains. In form it is very different from its neighbour, which is round and has no islands. We stood at a height of 16,033 feet, and therefore were 935 feet above the surface of Manasarowar. Then we rode down a valley clothed with brushwood, which emerges on to the flat, irregularly curved shore belt. Here are old, very plainly marked, shore lines, the highest 67.9 feet above the level of the lake. When the Langak-tso stood so high it had an outlet to the Sutlej, and the old bed of this river may be seen leading off from the north-eastern corner of the lake.
A strong south wind blew, and rolled the waves to the shore, where I sat a good hour, drawing and making observations. Then we rode again over the isthmus, at its lowest (15,289 feet) and broadest place. A salt swamp, begirt by hills, lies on its eastern half, quite close to the shore of Tso-mavang, with its surface 7.7 feet above that of the lake. In the sand and rubbish between the two are abundant streams of water, passing from the lake to the swamp. The swamp lies in a flat hollow of clay, in which the water evaporates, and the trifling quantities of salt contained in the lake water accumulate. At this place, then, the water of the eastern lake is prevented from seeping through to the western.
The following day we sailed with a favourable wind to the north-western corner of Tso-mavang, where Chiu-gompa stands on a pyramid of rock. This spot, camp No. 219, was to be our headquarters for several days. The outline of Tso-mavang is like that of a skull seen from the front, and we had now to explore the very top. A day of rest was devoted to a preliminary investigation of the channel where several cold and hot springs rise up; two of the latter had temperatures of 117° and 122° respectively, while in testing the third a thermometer graduated up to 150° did not suffice, and the tube burst. A spring of 117° in a walled basin is said to be used as a medical bath, but one must be a Tibetan to stew in water so hot. A small stone cabin beside it serves as a dressing-room. A little farther down the channel is spanned by a bridge constructed of four beams resting on two stone piers; it is in extraordinarily good condition, and is another proof that the canal contained water not so very long ago. On the piers of the bridge watermarks are still conspicuous 18½ inches above the present stagnant pools, smelling of sulphur and full of slimy weeds, which are fed by springs. Young wild-geese were swimming in one of them, and had great difficulty in protecting themselves from the brown puppy.
Chiu-gompa, the fifth of the eight monasteries of the lake which I visited, is small, and contains fifteen lamas who enter it for life, while the abbot is changed every three years. It owns some yaks, 500 goats, and 100 sheep, which are employed in transporting salt to Purang, where the monks barter it for barley. One monk, a youth twenty years of age, named Tsering Tundup, is one of the Tibetans whom I think of with particularly kind and warm feeling. His mother also lived in the monastery, and looked after the sheep and goats when they were driven in the evening into the penfolds. He was unusually handsome, refined, amiable and obliging, and showed me everything with full explanations. From his small bare cell he could dream and gaze at the holy lake in the east, and could see on the west Langak-tso, despised by the gods; but yet he was melancholy, and on that account we were sympathetic. He acknowledged openly that he was weary of the monotonous life in Chiu-gompa; every day was like the last, and the monks had hard work to procure a scanty subsistence, and must always be prepared for the attacks of robbers. It must be pleasanter to live as we did, and roam about freely among the mountains. He asked me if he might come with us, and I replied that I would willingly take him to Ladak. Then his face brightened, but he begged to be allowed to think over the matter until I returned from my next trip on the lake.
It rained all night, and in the morning everything was wet—even the things in my wind-beaten and torn tent, where little puddles had been formed. But Tsering came with the linen, so I was not so badly off. We had a long voyage before us, to camp No. 212, the first place we had encamped at on the holy lake. The programme of the excursion also included visits to the three other monasteries, the gauging of the volumes of water in the streams from the north, and the drawing of a map of the northern shore. We therefore took provisions for four days, which Rabsang and Adul were to transport along the bank on horses’ backs. We were to meet them at the entrance to the valley Serolung, at Serolung-gompa. This last voyage was to complete my investigation of the lake, but precisely because it was the last it was looked forward to with fear by my men. They thought that I had so long defied the god of the lake that now my time was come, and that he would avenge himself and keep me for ever.
But the morning was beautiful, and when at half-past five we rowed out over the smooth lake, the temperature was 48.6°. The cloud cap of Gurla extended down to the water, and nothing could be seen of the country to the south. The Pundi mountain was covered with snow and had a wintry appearance. At the first sounding-station (66 feet) the tents were seen as white specks hovering above the lake. Chiu-gompa stands proudly on its rocky point, and is a landmark visible from all parts of the lake shore except from the west. At the second station the sounding was more than 130 feet. Shukkur Ali and Tundup Sonam row like galley-slaves, for they hope to finish this line, and then the work will be at an end. Sometimes the boat passes through belts of foam and weed. At the fifth station (161 feet) the tents can still be seen with the glass, but after that they disappear. Gossul’s memorable monastery can also be dimly descried on its rock.
“Now we have traversed a third of the way,” I said.
“Thank God!” replied Shukkur Ali. “I hope the weather will hold up to-day.”