1871.] W. T. Blanford— Journey through Siklcim. > 383 



in Norway, terminating in the basin of a lake apparently hollowed 

 ont by itself.* 



After examining some of the huge rhubarb plants, the seeds of 

 which were unripe, and looking at some yaks which were browsing 

 in the little alpine valley by which we had ascended, we retraced 

 our steps and found our tents pitched in the broad valley we had 

 traversed in the morning, on a nice patch of dry turf, close to the 

 stream which runs down from the pass. We determined to halt at 

 this place for a day, and examine the neighbourhood. 



August 24th. It poured all night, and in the morning there was 

 snow on the peaks to the north of us, around the Yakla.f We 

 walked round the Bidan-Tso, which proved one of the best 

 examples of a glacier lake I have ever seen. Just at the upper or 

 north-west end, there is a horse-shoe shaped moraine, which has 

 formerly enclosed a second lake, now converted into a marsh. 

 At the south-east end of the Bidan-Tso is a second well marked 

 moraine, damming up the lake. From the end of the lake a 

 stream runs down into Biitan, the frontier of which is only a 

 mile or two distant, so that at this spot, the Sikkim, Butan 

 and Tibetan territories all meet. 



Birds were not numerous, and Raptores singularly scarce ; I only 

 once saw some vultures sailing far overhead. Once or twice swifts 

 appeared, doubtless Collocalia fuciphaga, which indeed I shot a few 

 days afterwards, and the Cashmere martin, Ghelidon Cashmiriensis, 

 was common. I once or twice saw the Nipal wren, Troglodytes 

 Nipalensis. In the scrub Trochalopterum affine, Phylloscopus lugubris, 

 and one or two other species, Merula albocincta and Propasser 

 thura were the principal birds ; and on the hill sides Calliope 

 pectoralis, Anthus rosaceus and Ruticilla frontalis. On the banks 



* There is a considerable similarity between these hollows and the " cirques" 

 of the Alps and Pyrenees. In the last number of the Quart. Jour. Geol. Soc, 

 1871, p. 312, the Rev. Mr. Bonney has shewn reasons for believing that such hol- 

 lows are due to the action of running water, and not to glaciers. But it is simply 

 impossible for running water to excavate a lake basin, and very difficult, so far as 

 I can see, for it to have formed the vertical cliffs which usually surround the 

 hollows. On the other hand Mr. Bonney is probably quite right in supposing 

 that these and similar results of erosion are due to a combination of different 

 causes, such as rain, streams, and glaciers, and not to one alone, but I cannot 

 help believing that glaciers have aided and very considerably aided in pro- 

 ducing the present contour. 



f La is a pass. 



