159 



IV. Digging Oil Wells. — The process for boring oil 

 wells is the same as has long been practiced for artesian 

 wells in France and in this country. When the rock, as 

 is generally the case, is covered with loose earth, this may 

 be removed by sinking a shaft with the pick and shovel. 

 But a more economical way and equally effective has been 

 universally adopted in the Pennsylvania oil regions. This 

 consists in driving an iron pipe down through the loose 

 earth by means of a pile driver, until it reaches the solid 

 rock. The iron pipe is usually about 5 or 6 inches in dia- 

 meter and in sections of about 8 feet in length. One sec- 

 tion is first driven down until the upper eno! is on a level 

 with the surface, then a second is set upon the top of this, 

 a flange keeping it in place, and the two are driven down 

 to a level with the ground, then a third and so on till the 

 first reaches the solid rock. Occasionally the pipe in being 

 driven meets some obstruction sufficient to break or deflect 

 it ; in that case the work must be abandoned. After the 

 pipe is driven, the earth is easily excavated by means of 

 an earth auger. When this is done the work of drilling the 

 rock begins. A derrick consisting of four posts, thirt}' or 

 forty feet long is erected, inclosing a space around the 

 boring of about 12 or 14 feet square. This when covered 

 furnishes a shelter for the workmen, and a support for hoist- 

 ing the drills, &c. The drilling is done by means of a strong 

 spring pole, fastened firmly at one end and free at the other. 

 To the free end the rod carrying the drill at its extremity 

 is fastened. The elasticity of the pole is sufficient to 

 sustain the weight of the drill rods. When the pole is 

 suddenly drawn down by force, the drill rod falls with a 

 severe concussion on the rock; this is repeated rapidly, and 

 the rock is gradually worn away. The debris of the rock 

 is removed from the hole by a sand pump. The spring pole 

 is worked either by steam, horse or man power. 



The depth to which wells require to be dug before reach- 

 ing oil is exceeding various. Col. Drake's well, the first 



