10 



SCIENCE. 



[N. S. Vol. XI. No. 262. 



of America and by various scientific jour- 

 nals. 



Among his writings are many discussions 

 of tlie character, sequence, extent and ar- 

 rangement of the geologic formations un- 

 derlying the State, and also of the deposits 

 of drift which mantle the surface. He de- 

 scribed in detail the geologic features of 

 many counties, and he worked out and pub- 

 lished the structure of most of the coal 

 fields of the State, discussing not only the 

 relations and extent of the seams, but their 

 practical qualities. During the last two 

 decades he gave great attention to the de- 

 velopment of petroleum and natural gas, 

 treating the scientific and practical aspects 

 of the Ohio fields with a thoroughness 

 which I believe to be without parallel. At 

 various times he studied and wrote upon 

 the building stones, limestones, iron ores, 

 rock water, gypsum and clays of Ohio and 

 other States, elucidating the geologic rela- 

 tions and usually pointing out also their 

 economic bearings. 



From the mass of material thus accessible 

 I select for special mention a single con- 

 tribution to pure and applied science, choos- 

 ing the one with which his name is most 

 frequently associated by brethren of the 

 hammer at home and abroad. I refer to 

 his study of the relation of gas, oil and 

 brine in subterranean reservoirs. It was 

 well known that the flow of oil from a well 

 is often preceded or accompanied by the es- 

 cape of gas ; it was known that the life of 

 an oil well was often terminated by the in- 

 flux of water, and that this water, when 

 derived from the same reservoir as the oil, 

 was highly charged with mineral matter ; it 

 was known that the static pressure of nat- 

 ural gas in a well was usually the same for 

 all wells of a group or district, and indepen- 

 dent of the altitude of the opening ; and 

 partial explanations of these facts had been 

 suggested by various students ; but it re- 

 mained for Orton to formulate a compre- 



hensive theory explaining all the phenom- 

 ena, and then, testing it by comparison with 

 a series of measurements and other observa- 

 tions in the gas and oil fields of northern 

 Ohio and Indiana, to place it on a sure and 

 enduring basis. Like many another result 

 of elaborate and successful investigation, 

 his theory, when stated, appears so simple 

 as to be almost axiomatic, and one is 

 tempted to wonder why the common sense 

 not only of geologists but of all concerned 

 in the development of petroleum and nat- 

 ural gas had previously failed of its attain- 

 ment ; and yet nearly every part of it has 

 been at one time or other the subject of at- 

 tack and controversy. 



Each stratum of porous rock containing 

 a profitable store of oil and gas is sealed 

 above by some impervious layer, so that 

 fluids cannot escape upward, though it 

 may communicate freely with the surface of 

 the ground at a distant point, if only the 

 communication involves an inverted siphon 

 equivalent to the plumber's trap. Under 

 these conditions the stratum constitutes a 

 reservoir in which three fluids arrange 

 themselves according to gravity ; gas oc- 

 cupies the pores of the upper part, and is 

 succeeded downward by oil, which in turn 

 rests upon water. If the stratum reaches 

 the surface of the ground at a place lying 

 higher than the reservoir, the water supplied 

 to it by rains exerts a pressure, in accord- 

 ance with the familiar hydrostatic law, on 

 the water in the reservoir, and this is com- 

 municated to the oil and gas. The gas is 

 compressed until its elasticity counterpoises 

 the weight of the column of water. If, now, 

 a well is drilled so as to tap the reservoir 

 at its highest point, gas rushes forth, being 

 forced out by the pressure of the water. If 

 a well reaches the reservoir in the zone oc- 

 cupied by oil, the oil is similarly forced 

 upward, and may be discharged at the sur- 

 face in case the pressure from the water is 

 sufficient. If a boring taps the reservoir 



