NATURE OF GAS PRESSURE. 197 



duits. But if it were possible to close up all of these exits (gas wells) 

 there can belittle doubt that the original pressure would finally return. 

 ( >f course in such a ease the water would crowd into the rock and en- 

 croach upon space hitherto occupied by gas until it had compressed the 

 remaining gas into a narrower compass and restored its original pressure. 



Application of the "Anticlinal Theory." 



This question of the cause of gas pressure is of more importance in 



connection with the geology of oil than might at first thought appear, as 

 will be subsequently shown. It was largely upon this theory of the 

 origin of gas pressure that I concluded that the Mount Morris oil belt 

 would, when traced south west ward, cross the Baltimore and Ohio rail- 

 way near Mannington, 25 miles in advance of any oil developments at 

 the time the prediction was made. My working hypothesis was that 

 since the gas pressure is due to a column of water, and since this must 

 he practically the same for any limited area where the rock lies at the 

 same depth below sea level, the oil deposit in this particular rock must 

 extend across the country along the strike of the beds, in a pool com- 

 parable to the surface of a lake or a chain of small lakes, if the rock reser- 

 voir should not he equally porous everywhere along the strike. Hence, 

 if my theory is true, it would only be necessary to follow the strike of 

 any particular coal bed, limestone, or other stratum outcropping where 

 the oil was actually developed in order to trace the course of the oil belt 

 upon the surface, and thus to determine with approximate accuracy, 

 many miles in advance of the drill, the location and width of such possi- 

 ble oil territory. Very fortunately for my purpose, two persistent coals. 

 tin- Waynesburg and the Washington beds, cropped to the surface at 

 Mount Morris, the first well finished there by Mr. E. M. Hukill, in Octo- 

 ber, 1886, stalling immediately on top of the Waynesburg scam. 



My firsl work was to determine the tide elevation of these coal beds, 

 especially the Waynesburg, with reference to oil, gas and salt water as 

 developed by the Mount Morris borings. For this purpose one of my 

 associates. Profess >r T. M. Jackson, then professor of civil engineering at 

 the West Virginia university, ran a line of levels from the Monongahela 

 river (using a Baltimore and Ohio railway datum) out to the oil held, 

 and made a complete survey and map of the twenty or more wells that 

 hail been drilled nt that time i .la unary. L889) in and about the village of 

 Mount Morris. He also obtained the elevations of the coal beds a1 every 

 possible point. From the data thus acquired it was learned that wher- 

 r t he Waynesburg coal lias an elevation of 950 feet above tide. -a-, and 

 not oil, was found, and that where it had dipped down belov> 870 feel 

 salt water was a certainty in the Mount Morris region at least, A- : 



