Corning Oil Company. Denman & Thompson. O’Connel Oil Company. Brooks Oil Company. Caldron & Snyder. Sunday Creek Oil & Gas Company. Perry County Oil Company. W. B. Barker & Company. Cleveland Oil Company. Keystone Oil Company. W. E. Detlor. William Rosier. J. H. Van Wormer. Northeast Oil Company. Becker Oil Company. Allen, Sternberg & Company. Bolivar Oil Company. William McMullen. A. Bulger & Company. Corning Natural Gas Company. L. D. Langmade. Harrington Brothers. Ohio Oil Company. Church Oil Company. Monroe Oil & Gas Company. Weaver Brothers. W. B. Irwin & Company. George Best & Company. Foster & Moran. Fallen Rock Company. Ohlviler & Chambers. Mill Oil Company. Hemlock Oil Company. John Holden. Wells & Foraker. Longfellow & Stevens. Russell Metzger. McGee & Stewart. Stratton & Mark. National Oil Company. GEOLOGY OF THE REGION.—The surface of the territory lies in the Lower Productive and Lower Barren coal measures. The highest hills reach up to or extend above the Ames or Crinoidal limestone. In fact along the northeast extremity of the field the hills are capped by the limestones which underlie the Pittsburgh coal. The deepest valley—that of Sunday Creek—cuts through the Middle Kittanning coal, a short distance north of Corning, but at this town the seam named is under cover, while the Upper Freeport coal is at about drainage level. The succession of strata under ground is shown by the following record kept and furnished the Survey by Mr. G. W. Delong, Superintendent of Schools, Corning. The well is located on lot 154 of the town just named, and the top of the well lies at the base of the Mahoning sandstone: Thickness of Total Stratum Thickness