IOWA ACADEMY OF SCIENCES. 
43 
the record of an old water well near Yale, where a forest bed 
some three feet in thickness was passed through. It was over- 
laid by forty-two feet of yellow, blue and red clay and beneath 
was four or five feet of blue clay. Below the latter there is from 
two to ten feet of sand. The gas at Herndon is found in a layer 
of sand at the base of the drift and probably directly overlying 
the coal measure shales. 
During the past summer the wells near Dawson were visited 
and a few additional facts secured concerning them. Dawson 
is located near the northern border of Dallas county and about 
eight miles east of Herndon. The wells are three-quarters of 
a mile south of town and the gas occurs under much the same 
conditions as at the locality already mentioned. Five holes 
have been drilled here, one being put down in 1888 and the 
other four in 1891. They have a depth of from 110 to 115 feet, 
passing through the drift clay into a bed of sand and gravel. 
The gas is found in the gravel layer below a compact blue clay. 
A coal shaft just east of Dawson shows sixty -four feet of this 
blue clay. During the past summer the first well, bored eight 
years ago, was tested to find the pressure, the result being that 
this was ascertained to be 24 to 25 pounds to the square inch. 
The gas burned with a flame 15 to 20 feet high. It was piped 
to town, and for a time supplied one of the houses with fuel. 
It was also used in the kilns of a brick plant a short distance 
east of the station. Three of the wells still have a good flow 
but are no longer used. 
In this connection mention should perhaps be made of the 
gas found in considerable quantity in the water supply of 
Perry, six miles east of Dawson. Perry secures its supply 
from four wells located in the southern part of town. These 
wells have a depth of 115 feet. Gravel is struck 70 feet below 
the surface and the lower 45 feet is through this material. The 
water for a time came to the surface and overflowed, but after 
a number of wells were sunk and it had been pumped from the 
city wells the head was lowered, and now the water rises only 
to within 5 or 6 feet of the surface. The amount of gas in the 
water is so great that Mr. J. W. Rodefer has for some time 
been experimenting for the purpose of extracting it for use in 
heating and lighting. He has succeeded in doing this on a 
comparatively small scale, and the gas thus separated is utilized 
to furnish fuel and light to his office. Can it be extracted by a 
sufficiently inexpensive method, and in large enough quantity, 
