122 BULLETIN UNIVERSITY OP MONTANA 



The snow mass behind the spur to the left in Plate XXXV. flows into a 

 small and beautiful lake, Leash lake. This lake is said by those who 

 have seen it to be of surpassing beauty, usually full of snow, and visible 

 only when almost upon it, so well is it hidden in the cliffs. The water 

 entering the lake flows down the side of McDonald northward. After 

 leaving Leash lake the water flows west, coming down and joining the 

 stream from Teton on the north and the stream from the west glacier of 

 McDonald. 



Post creek, the outlet of McDonald lake, on the 30th of June, 1900, 

 carried 473 second feet of water. The place at which the water was 

 measured was some miles down creek from the lake, at a lower elevation 

 than the lake by a thousand feet, and with considerable loss between placa 

 of measurement and lake through irrigation. 



