1877.] 4^" [Carll. 



On the First Systematic Collection and Discussion of the Venango County 

 Oil Wells of Western Pennsylvania. By E. 8. JSfetfleton, C. E. Pre- 

 pared for publication and communicated by John F. Carll, Assistant 

 Geologist in charge of the Survey of the Oil Begions. 



{Bead before the American PhilosopJdcal Society, January 19, 1877. ) 



In the fall of 1868 the first systematic attempt was made to ascertain the 

 direction and dip of the Oil Sands of the Venango region and the true re- 

 lation which the oil producing rock of one district bears to that of another. 



This was during the great Pleasantville oil excitement, when, probably 

 for the first time, the attention of a large class of operators was called to the 

 fact that there was a marked difierence between the oil and oil sand of 

 Pleasantville and surrounding districts, and the oil and oil sand of Oil 

 Creek. 



Previous to that time very few levels had been taken, and those only 

 locally from well to well on the same farm, or within the bounds of one pro- 

 ducing centre ; but some of the detached districts had been fortuitously con- 

 nected hy lines of levels run for pipe lines from station to station, and by 

 preliminary Railway surveys which crossed the country in almost every 

 direction. From these sources it was ascertained that the Pleasantville oil 

 rock, although called the 4th sand, lay at a higher elevation than the 3d 

 sand of Oil Creek. 



Some operators held the opinion that the oil rocks ran horizontally under 

 the whole country, and that by drilling deeper at Pleasantville, the Oil 

 Creek 3d sand would be found, and a much larger supply of oil obtained. 

 Others contended that the rocks dipped towards Oil Creek and the Pleasant- 

 ville wells had already reached the Oil Creek sand. They went still furtlier, 

 and pointing to the old failures in the Pleasantville district, averred that 

 there was no oil in the rock when these wells were put down, but that 

 the flooding of the oil sands under the valley of Oil Creek, by the abandon- 

 ment years before of so many wells, had forced the oil from its original 

 home there to these higher portions of the rock. 



Discussions on these points sliowed the necessity foi- more information on 

 the subject; and Avhile some cliose to gain this information on their own ac- 

 count, by sinking wells deeper at considerable expense to see what might be 

 below, a few believed that something could be learned by a careful study 

 of the wells already drilled, in connection with a series of surface levels 

 extending over a large area, embracing in one system all the main oil- 

 producing centres. 



As an outgrowth of this idea an informal meeting was held and a com- 

 mittee appointed to plan and carry out the work necessary to be done. 

 Mr. E. S. Nettleton, then residing in Pleasantville, consented to act as one 

 of the committee, and to undertake the task of running the lines of levels 

 and collecting the well records. A circular was issued to well owners, and 



PROC. AMER. PHIL08. SOC. XVI. 99. 3b 



