OKIGIN AND USE OF NATURAL GAS AT MANITOU. 17 



ous matter covered the floors and tilled some of the passage- 

 ways of the caves. The springs are found at three points in 

 the valley, and these places are at the apices of a triangle 

 roughly equilateral. The group including the Navajo, Mani- 

 tou. Cheyenne and Shoshone, which lies in the center of the 

 town, and forms the eastern end of the triangle, has the 

 largest flow of water and gas. The eastern of the two trans- 

 verse rock flexures occurs at this point. West of this group 

 the valley widens and divides, and the Ute Iron spring is 

 found in Engleman's Canon, a short distance above its mouth, 

 and almost in the granite. The third position, that of the 

 Hiawatha group, is in the general line of the valley, near 

 the limestone rocks, and not far below the entrance to 

 the Ute Pass. It is said by old residents that the largest 

 spring was not many years ago found at this place, but that 

 it was deeply covered and quite obliterated by deposits of 

 gravel brought down the Pass during a severe freshet. In the 

 neighborhood of each group of springs the gravel and wash 

 has been cemented by a tufaceous substance deposited from 

 the waters and called locally "soda-rock." The Navajo group 

 and the Ute Iron spring are near to the line of contact of the 

 granite with the sedimentary beds; the Hiawatha group is 

 near the line of the Ute Pass fault. In all cases the springs 

 lie close to the streams, and in the creek bed near some of 

 them, numerous small vents are shown by rising bubbles of 

 gas. 



The rain and snow descending upon the earth bring with 

 them matters washed from the air, and after reaching the 

 ground the waters dissolve portions of all the soil and rocks 

 over which and through which they make their way. It is 

 therefore natural to seek in the waters of these springs for 

 evidence concerning the rocks they have traversed, and thus, 

 if possible, trace nearer to its origin the accompanying gas. 

 The following analyses of water from several of the more im- 

 portant springs were made by Prof. Elwyn Waller, Ph. D., of 

 New York, from sami)les taken from the springs by the writer 

 in the summer of USUI. These results have been confirmed 

 by analyses made in the laboratories of Colorado College on 



