126 THE GREAT NORTH-WEST 



A very remarkable meteorological circumstance was 

 noticed several times during the winter. At a distance 

 of about five miles from our hut a belt, or current, 

 of warm air was observed to frequently blow across 

 the plain. The wind on such occasions was always 

 in the west, varying a point or two south, and I inferred 

 that the current referred to found a passage through the 

 Rocky Mountains direct from the Pacific. It is difficult 

 to surmise how otherwise a warm current should be 

 perceivable in these regions. The warmth was very 

 perceptible, one appearing to pass right into it at once 

 from a low temperature. There was often a partial thaw 

 within the belt affected by this air, which was about ten 

 miles wide. The temperature within this distance seemed 

 to be about the same. We noticed when we entered and 

 when we left it and that this was no fancy was proved 

 by the fact that the vegetation showed, in a perceptible 

 degree, a superiority of development compared with the 

 forest outside its limits. Doubtless this phenomenon has 

 been noticed by other travellers, and possibly it is fully 

 accounted for ; but I have not myself seen it mentioned 

 in any work I have read. Achil said that he had per- 

 ceived it much farther to the west, and that there the 

 belt seemed to be wider, and he had heard from the 

 Indians accounts of a region to the south-west where the 

 climate was always more genial than in this or other 

 parts of the great North- West. 



I made several journeys with the object of learning 

 the extent and direction of this current. It traversed 

 the district from south-west by south, in a curve, to 

 about north-east by south, but was only perceptible with 

 westerly winds. Its longitudinal length it was impossible 

 to conjecture, but the width was not greater than ten 

 miles ; often it was only four or five. The increase of 

 temperature was first noticeable just where the graves of 

 the two trappers (as I presume them to have been) were 

 made. Within these bounds mosquitoes, or gnats, were 



