thresholds which lie athwart the stream as a variety of modified shore-line, which owe their existence to the shrinking of the lake; so that they furnish yet another proof that this lake actually is contracting in area. Nevertheless it would be incorrect to compare the recently mentioned strand-ramparts with these thresholds; the
FROM CENTRAL TIBET TO LADAK.
two sets of phenomena are quite different. For at the time when the Selling-tso shrank so as to touch only the lowest of the seven ramparts, the thresholds in the river-bed were situated a considerable depth below the level of the lake. They are no doubt underground sandstone ridges in the lake basin, now for
Fig. 24. FISHING IN THE JAGJU-RAPGA.
IIIF Color HighRes
