NO. 15 



SMITHSONIAN EXPLORATIONS, I92I 



21 



and soft bands of limestone and shale of the Sullivan ' formation, and 

 they form a somewhat unique topographic feature, and are the top of 

 the world at this point. 



Thompson Pass is one of the scenic features of the Continental 

 Divide when viewed from the high Alpine valley on the northeast side 

 of Castleguard Canyon. The Pass is low (6,511' or 1,984 m.), and 

 bold high ridges lead up to mountain summits on either side (fig. 4). 

 A view taken on a misting day shows Watchman Lake (6,050' or 



Fig. 24.- — A snowy morning on upper Pipestone River. 



1,844 ^'^■) ^tid above it Cinema Lake (6,400' or 1,950 m.) on the north- 

 east slope of the Pass. On the south Watchman Peak (8,674' or 

 2,634 m.) which lies in front of Mount Rice (10,745' or 3,275 m.) 

 and on the right Mount Bryce ( i i.ooo' or 3,352 m.) and Bryce glacier, 

 which is at the head of the middle branch of Castleguard River. The 

 Castleguard glaciers flow down from Mount Castleguard (10,090' or 

 3,075 m.), which is a fine peak a few miles northeast of Mount Bryce. 

 Figure 4 is a fine illustration of a misting day along the Continental 

 Divide. We were camped for a week on the south side of the Alpine 



^ Smithsonian Misc. Coll., Vol. 72, No. i, 1920, p. 15. 



