30 TEE POPULAR SCIENCE MONTHLY 



out. During that interval there had been no change in conditions ex- 

 cept that the region had been stripped of forest and numerous rude 

 country roads had been made. There was no railroad, except at the 

 extreme north; there were no extensive mining operations except on 

 the Pittsburgh coal bed on the Monongahela Eiver, and there were no 

 records of oil borings except in the southeast corner where they were 

 not needed. To add to the natural drawbacks, we were equipped with 

 aneroids which were fearfully and wonderfully made. Lesley, unable 

 to induce Becker to make a supply of high grade barometers, had pro- 

 cured a number of models to be tested. Those assigned to us were 

 shaped like a hat box and were provided with vernier and other attach- 

 ments, all of which had to be cared for at each reading, as otherwise 

 the observation would be wholly worthless. Happily for us, our horses 

 ran away one day; when the race was over and White's horse had won, 

 we discovered with grateful hearts that the barometers were ruined. 

 Thereafter we used our own barometers, which proved to be fairly good. 



As soon as we had passed beyond 100 feet above the "Waynesburg 

 coal bed, satisfactory exposures became rare — and nine tenths of Greene 

 County, in which we had begun, was above that horizon. The only 

 recourse was to examine every bit of rock that jutted out on a hillside. 

 Sections were made everywhere, 5 to 100 or more feet long, but the 

 longer ones had tormenting gaps which refused to be filled. Strange 

 anomalies appeared, which cast doubt on tentative correlations; lime- 

 stone was found where we expected variegated shale; streaks of coal 

 appeared in what seemed to be wrong positions; sandstone was seen 

 where there should have been a coal bed. Our work proved that these 

 are not anomalies and the conditions are commonplaces to-day; but 40 

 years ago the continuity of deposits was a cardinal doctrine and all 

 limestones were marine. Our conversion was slow but it came, and 

 little by little we were able to piece the fragments together; the sec- 

 tion was completed as far as possible and doubt remained respecting 

 only a few horizons, which were not economically important. 



It would have been well if several localities could have been re- 

 examined; a number of errors would have been eliminated which now 

 are so evident that any one can note them. Ee vision is very different 

 from original work, and is a very simple matter. If the original ob- 

 server has recorded his observations honestly, the reviser needs no 

 especial acumen in order to discover the errors. If White and I had 

 had the advantage, 40 years ago, of the hundreds of oil-well records 

 made in the Greene and Washington district during the last 20 years, 

 our work would have been a holiday jaunt; we should not have been 

 compelled to spend so many dreary days in securing fragmentary sec- 

 tions or so many weary nights in trying to combine them. But there 

 were no well records and there was no opportunity for revision. Too 



