322 HISTOEY OF PETROLEUM OR ROCK OIL. 



It also occurs in similar conditions in the ClifiF limestone (Devonian) 

 of Ohio. 



Higher still in the series, at the base of the Hamilton group, occur 

 what in New York have been called the Marcellus shales; these en- 

 close septaria or concretionary nodules which contain petroleum, 

 while at the summit of the same group similar concretions holding 

 petroleum are again met with. The sandstones of the Portage and 

 Chemung group in New York are in many places highly bituminous 

 to the smell, and often contain cavities filled with petroleum, and in 

 some places seams of indurated bitumen. A calcareous sandstone 

 from this formation at Laoua, near Fredonia, in Chatauque county, 

 contains more than two per cent, of bituminous matter. At Rock- 

 ville, in Alleghany county, according to Mr. Hall, the same sandstones 

 are highly bituminous and give out a strong odor when handled, and 

 in the counties of Erie, Seneca, and Cattaraugus abundant oil springs 

 rise from the sandstones, and have been known to the Seneca Indians 

 from ancient times. In the northern part of Ohio, according to Dr. 

 Newberry, petroleum is found to exude in greater or less quantity 

 from these sandstones wherever they are exposed, and the oil wells 

 of Pennsylvania and Ohio are sunk in these Devonian sandstones, 

 often through the overlying carboniferous conglomerate, and in some 

 cases apparently, according to Newberry, through the sandstones 

 themselves, which are supposed by him to be only reservoirs in which 

 the oil accumulates as it rises through fissures from a deeper source; 

 in proof of which he mentions that in boring wells near to each other 

 the most abundant flow of oil is met with at variable depths. In some 

 instances the petroleum appears to filter slowly into the wells from 

 the porous strata around, which are saturated with it, while at other 

 times the bore seems to strike upon a fissure communicating with a 

 reservoir which furnishes at once great volumes of oil. An interest- 

 ing fact is mentioned in this connexion by Mr. Hall. In the town of 

 Freedom, Cattaraugus county. New York, is a spring which had long 

 been known to furnish considerable quantities of petroleum. On 

 making an excavation about six yards distant, to the depth of fourteen 

 feet, a copious spring of petroleum arose, and for some time afforded 

 large quantities of oil ; after which the supply diminished in both the 

 old and new springs, so that it is now less than at the first settlement 

 of the country. Notwithstanding its general distribution throughout 

 a considerable region in the adjacent portions of New York, Penn- 

 sylvania, and Ohio, it is only in a few districts that it has been found 

 in quantities sufiicient to be wrought with profit. The wells of Mecca, 

 in Trumbull county, Ohio, have been sunk from 30 to 200 feet in a 

 sandstone which is saturated with oil ; of 200 wells which have been 

 bored, according to Dr. Newberry, a dozen or more are successfully 

 wrought, and yield from five to twenty barrels a day. The wells of 

 Titusville, on Oil creek, Pennsylvania, vary in depth from TO to 300 

 feet, and the petroleum is met with throughout. The oil from difler- 

 ent localities varies considefably in color and thickness, and in its 

 specific gravity, which ranges from 28° to 40° Baume, (from .890 to 

 .830.) 



