Ohio Natural Gas Fields. — Bozvnockcr. 229 
The table shows plainly the short life of wells in the best 
territory, where care is taken to prolong their lives. Since the 
rock pressure of the field is now much lower than it was a 
few years ago, it follows that wells drilled hereafter will be 
much shorter lived than those sunk formerly. 
Salt Water. — Operators and drillers are almost a unit in 
reporting the gas sand free from water. However, the great 
limestones lying above the Clinton rock are charged with brine 
in the Sugar Grove field, and this is a constant source of dan- 
ger, for unless the packer fits tightly the w^ater crowds into the 
sand, causing serious trouble, and sometimes ruins the well. 
Around Homer, as has already been stated, no water is foimd 
below the Berea grit, and consequently the danger is much 
smaller. 
Rock Structure. — The strata in the Sugar Grove field have 
been considered by some on a priori grounds to^ form an anti- 
cline, and by others a terrace. Neither, however, appears to 
be correct. On a line running almost due east and west through 
Sugar Grove, the rock dips to the east nearly 260 feet in less 
than six miles, an average of forty-five feet per mile, barom- 
eter measurement. 
This shows neither an arch nor terrace extending through 
the territory north and south. Further, at the village Amanda, 
eleven miles west of Sugar Grove, the Clinton rock lies 600 
feet higher than it does at the last named village. This ex- 
cludes a possible suggestion that the gas belt may lie in the 
eastern slope of an arch, as several reservoirs of oil and gas are 
known to do in eastern Ohio. 
From Lancaster the rock dips southeast more rapidly than 
the bed of the Hocking river slopes, as is shown by the increas- 
ing depth of the wells in the valley of this stream. This ex- 
cludes the idea of an east and west arch or terrace. 
The large reservoir known as the Sugar Grove, may be re- 
garded as consisting of several small but contiguous ones. 
This is well illustrated by changes in rock pressure. Thus the 
rock pressure at Lancaster has long been nil, while the wells 
on the Zink farm, two miles north of that town, which were 
drilled in 1891, still have a pressure of from 500 to 600 pounds 
per square inch. Around Sugar Grove the pressure has dropped 
to 100 pounds, but a few miles away it is several times that 
