IOWA ACADEMY OF SCIENCES. 97 



considerable extent; in one case an acre or more of this same 

 soft rock, evidently formed by the springs. One spring is 

 heavily charged with iron; another is called milk spring, soda 

 spring, sulphur spring, etc., all within easy distance, of each 

 other. Some springs have a sort of periodic flow. 



Particularly is this true of one which sounds very much 

 like the puffing of a steamboat. 



At the eastern end of the village is a spring issuing from 

 fissures in what seems to be a volcanic rock. The water of 

 this spring has a temperature of 108 degrees F. Close by this 

 spring is a very neat and convenient bath house, with nice 

 large pools for swimming. The water here is abundant, and, 

 at first, seems almost too hot for comfort, but it soon becomes 

 delightful. It contains a small amount of hydrogen sulphide. 

 Seven miles northwest of the village, in a very wild and unfre- 

 quented region, we visited what are known at the Springs as 

 the Hot Springs. Here the water has a temperature of 160 

 degrees F., so we were told; we forgot our thermometer at Ft. 

 Collins. In about twenty minutes it cooked eggs for us. 

 These springs are within a rod or two, on either side, of a 

 delightful little mountain stream. They issue from fissures in 

 a dark, fine-grained rock, already referred to as resembling 

 diorite, or basalt. In one of the hills mentioned above, formed 

 by the springs by the Bear, is a small cave. On descending 

 into this cave, I had my first serious encounter with carbon- 

 dioxide. It was wholly unexpected, and for a few moments I 

 could not realize why I could not breathe. Other members of 

 our party went into the cave, cautiously, to convince them- 

 selves that there was an unbreathable gas present. In the 

 bottom of this cave is an incrustation of what appears to be 

 sulphur. 



There are abundant reasons for believing that the springs 

 in and around this village are on the decline. Places where 

 springs must have been strong and vigorous, in very recent 

 geologic time, now show no signs of life. Such places are 

 numerous. How rapidly such changes are taking place here 

 now, we did not attempt to determine. 



Steamboat Springs is probably a little over 6,000 feet above 

 the sea. Every night, while we were camped at the village, 

 water froze in our buckets, and particularly, on the morning of 

 July 24th, so much ice was formed in our buckets and about 

 our mess box, that, judging from like conditions at Muscatine, 



