stopped by removing the scattered trees, by 

 burning the frail bridges that enabled the fire to 

 travel from one dense forest to abundant fuel 

 beyond. In a city it is common to smother a fire 

 with water or acid, but with a forest fire usually 

 it is best to break its inflammable line of com- 

 munication by removing from before it a width 

 of fibrous material. The axe, rake, hoe, and 

 shovel are the usual fire-fighting tools. 



A few yards away from the spot where the 

 fire started I found, freshly cut in the bark of 

 an aspen, the inscription: 



JSM 



YALE 18 



A bullet had obliterated the two right-hand 

 figures. 



For days I wandered over the mountains, go- 

 ing from fire to smoke and studying burns new 

 and old. One comparatively level tract had been 

 fireswept in 1791. On this the soil was good. 

 Lodge-pole pine had promptly restocked the 

 burn, but these trees were now being smothered 

 out by a promising growth of Engelmann spruce. 



