HAWORTH. | Gas Pressure. | 183 
the standpoint of geology, it must be said that there are good 
reasons for expecting great gas-fields will be developed in the 
future, as in the past. Only a small fraction of our territory 
has yet been prospected. No one can bring forward any rea- 
sons for considering the fields already developed more fortu- 
nately located than other areas not yet tested. 
On Pressure in Gas-wells. 
Why does gas exert such a pressure in gas-wells? Why does 
the pressure in gas-wells decline with use? These two ques- 
tions are asked frequently, and occasionally attempts are made 
to answer them. If we could know the origin of gas, how na- 
ture manufactured it, and how it is transported to its present 
hiding-places, possibly we could answer the questions just 
asked. In the early days of gas-wells in the Appalachian re- 
gion it was assumed that in some way the rocks yielded as 
though made of compressible materials and that by so yielding 
the pressure in some way was set up and, hence, the term “rock 
pressure” became incorporated into our language and still re- 
mains in common use with the great majority of oil and gas 
men. Some geologists were led to believe the same and, in a 
few instances, even defended the proposition. More recently, 
however, it has been concluded by geologists generally that 
the rock masses do not yield to pressure; at least do not in the 
way previously considered, and that therefore the term “rock 
pressure” is a misnomer. ~ 
The next general opinion expressed was that gas pressure is 
caused by water pressure, the assumption being that rain- 
water constantly falling upon the surface of the earth is as 
constantly penetrating into the earth and tending to drive out 
from rock voids oil and gas and whatever else may be present 
lighter than water. Under this conclusion pressure on gas 
in wells ordinarily should be proportional to their depths. The 
late Professor Orton, in studying certain wells in southwestern 
New York, found that the pressure exerted by the gas was 
greater than could be caused by a column of water with a 
height equal to the depth of the well. Consequently, he aban- 
doned this idea and gave us nothing in return. Dr. I. C. White, 
in his estimable report on oil and gas for West Virginia, refers 
to this and concludes the explanation should be that nature 
has manufactured so much gas in a given place, and that the 
pressure is dependent upon the amount of gas manufactured in 
