206 ON THE FEONTIEE. 



safety ; and so the wearisome work of alternately trampling 

 a path for the animals was recommenced. 



" Our point of destination was south of us, so southward 

 we turned our steps ; and before we had gone very far I 

 noticed in a depression to our left a few osier switches ; 

 farther on, where the depression became more considerable 

 and clearer defined, there was a solitary and gnarled 

 dwarfed willow ; still farther, some more ; then the de- 

 pression, becoming wider and deeper, swung round to the 

 right behind a knoll which hid its further course from our 

 sight. The inference was unmistakable. The hollow was 

 but the commencement of one of the outlets of the drainage 

 of the plateau, and most probably one of the sources of 

 the first confluent which joined to the south of us the river 

 below. 



" That this was so, I soon felt convinced ; the hollow de- 

 scending with increasing steepness, and at length a turn 

 brought us to a wide opening through which the San Luis 

 Valley and distant mountains were again visible, and the de- 

 pression in the ground we were in changed to a steep rocky 

 groove, gradually enlarging in its descent until it became a 

 winding canon which joined the plain below. The place was 

 probably the continuation of the Mosca Pass ; at any rate, I 

 determined to there attempt the descent of the mountain. 

 The lower part of the canon appeared to be thickly wooded, 

 the timber extending far up the side of the mountains, and, 

 but a short way below where we were, groves of quaking 

 aspens appeared. 



" For the first few miles of our way the declivity was a 

 very sharp one indeed ; but that rendered travelling through 



