480 POPULAR SCIENCE MONTHLY. 



grizzly was so recent a victim that his tracks were still visible in the 

 white, earthy slopes, leading clown to the spot where he had met his 

 death. In no case were any marks of violence seen, and there can 

 be no question that death was occasioned by the gas. The wind was 

 blowing directly up the ravine during our visit, and we failed to 

 get any test for carbonic acid, though we exhausted all our matches 

 in the effort, plunging the flames into hollows of the rill bed in vari- 

 ous parts of its course; they invariably burned brightly, and showed 

 not the slightest tendency to extinguish. The dilution of the gas in 

 such a breeze would be inevitable, however; that the gas was present 

 was attested by the peculiar oppression on the lungs that was felt 

 during the entire period that we were in the gulch, and which only 

 wore off gradually on our return to camp. I suffered from a slight 

 headache in consequence for several hours. 



There was no difference in the appearance of the portion of the 

 gulch where the eight bears had met their end and the region above 

 and below. A hundred yards or more up stream the solfataric de- 

 posits become less abundant, and the timber grows close to the brook; 

 a short distance beyond this the gulch ends. No bodies were found 

 above, and only bears were found in the locality described. It will 

 be observed that Weed's experience differs in this respect from ours, 

 and the appearance of the place was somewhat different: he found elk 

 and small animals in addition to the bears, and describes the death- 

 trap as occupying the mouth of the basin at the head of the gulch, 

 above the point where the last springs of acid water cease. The 

 rill observed by us has its source far above the animals; indeed, it 

 trickles directly through the worm-eaten carcass of the cinnamon 

 bear — a thought by no means comforting when we realized that the 

 water supply for our camp was drawn from the creek only a short 

 distance down the valley. 



It is not impossible that there may be two or three of these 

 gullies having similar properties. That we should have found only 

 bears may perhaps be accounted for on the ground that the first 

 victim for this season was a bear, and his carcass frightened away 

 all animals except those of his own family. For an illustration of a 

 process of accumulation of the bones of large vertebrates, with all 

 the conditions present necessary for fossilization, no finer example 

 can be found in the world than Death Gulch; year after year the 

 snow slides and spring floods wash down this fresh supply of en- 

 trapped carcasses to be buried in the waste cones and alluvial bot- 

 toms of Cache Creek and Lamar River. Probably the stream-formed 

 conglomerate that we noted as we ascended the creek is locally filled 

 with these remains. 



The gas is probably generated by the action of the acid water 



