Devonian Era in the Ohio Basin. — Claypole. 99 
depth of about fifty feet, when the auger was unable to sink any farth- 
er on account of the enormous pressure of the escaping gas. 
The second section — at Fostoria — also begins in the Lower Helder- 
berg limestone, but the strata in the upper portion were not well dif- 
ferentiated in the record. The Trenton was here penetrated to the 
depth of 500 feet in the hope of finding additional supplies of gas, but 
without success. 
In the next section — at Tiffin — the upper strata were not carefully 
noted and the top of the Trenton was only slightly penetrated. The 
Ohio shale first appears in the boring at Plymouth, where it is overlain 
by the Berea grit and, including the Bedford, reaches a thickness of 
648 feet. At Berea, this has risen to 1240 feet; at Akron, to i860; at 
Ravenna, to 1990; at Nelson Ledges, to 2000; while at Youngstown 
the auger passed through 2280 feet of the shale without reaching its 
base, and at East Liverpool, some miles farther south than any of the 
foregoing places, 2454 feet of drilling failed to pierce it. 
Passing into Pennsylvania, we may state, in a word, that no bore- 
hole in the oil regions has ever reached the Corniferous limestone, so 
that the whole thickness of the shale is there altogether unknown. But 
in Crawford county, Prof. White's generalized section shows from the 
'base of the Berea grit or the Corry and Cussewago sands, to the bot- 
tom, 1265 feet. The Cobham well, in Warren county, revealed 
about a thousand feet of sandy shales in the same position. The Dennis 
well, in MacKean county, after having found 132 feet of Pocono 
sandstone (the equivalent of the Berea) penetrated about 1587 feet of 
sandstone and sandy shales assigned to the Catskill and Chemung. In 
Potter county, a bore was started in the last-named stratum and was 
sunk through 1995 feet of sandy shales and shaly sandstone without 
reaching the bottom of the mass. 
But all these records are distanced by that of the famous Watson 
well, at Titusville, the scanty details of which are apparently trust- 
worthy so far as the main facts are concerned, though it is a matter of 
lasting regret to geologists that the section of this, the deepest well in 
that part of the state, has been irrecoverably lost. Here the auger, 
leaving the Pocono at the depth of 100 feet, penetrated 3433 feet of al- 
ternating hard and soft beds until the work was stopped at 2263 feet 
below the ocean level, in a black shale which was probably the bed 
immediately overlying the Corniferous limestone. It is almost certain 
that this stratum would have been reached in a very short distance 
more and the problem for that region finally solved. 
Obviously the Ohio shale, excluding the Bedford, is the homologue 
of the great Genesee, Portage and Chemung series of New York and 
eastern Pennsylvania. To the^e may be added Catskill, which is mere- 
ly a local, but immense sandy development of the upper portions of the 
same. The intercalation of sandy beds to the eastward and the increas- 
ing sandiness of the shale are evidence of the comparative nearness 
of the Devonian, and the immense increase in thickness indicates as 
