The sand rock of Pithole, though unusually productive, had a small area in comparison with beds of more recent discovery. The Frazier and Grant wells flowed at the rate of 700 and 450 barrels a day. The sand rock on the flats of Pithole creek is 14-20 ft. thick, and at 600 ft. The chief centres in this district are :-1. Cash Up, though of small extent, was remarkable for its yield ; the 1st well when drilled deep gave 1100 barrels a day. 2. Bean Farm had small wells, but proportionately lasting. 3. Bull Run and Cow Run are underlaid with a highly productive sand rock ; the famous Noble well here gave 2500 barrels a day.
The Petroleum Centre oil claims overlie a fine bed of sand rock, 45 ft. thick, at 950 ft.
At Story Farm, over 180 wells, producing nearly 1 million barrels of oil, were drilled within 500 acres. The territory is now exhausted. The sand rock here is 40-45 ft. thick, at 480 ft. On the Blood, Rynd, and Tarr farms, the sand rock is 38-58 ft. thick ; it has yielded enormously in former times, some of the wells giving 1000-4000 barrels a day.
Rouseville wells have struck the 3rd sand, 27-42 ft. thick, at 550 ft. ; four wells on a single acre have given over 100,000 barrels of oil. The valley of Oil Creek, after producing over 110 million dollars' worth of oil from an area of less than 3 sq. miles, obtained with extraordinary waste, is rapidly declining.
At Oil City, along the creek and river-flats, fairly productive wells have been found, the 3rd sand being 20-55 ft. thick, at about 475 ft.
At Reno, the sand rock was found on the Charley Run at about 500 ft. On Sage Run, the sand rock is 18-20 ft. thick, at 900-1000 ft., and the wells have yielded up to 300 barrels each daily.
The wells of Franklin and Sugar Creek find their oil iu the uppermost oil-producing sand rock on the great slope from the north-west. The rock is met with at a depth of 260 ft., beneath the flat; it is geologically higher than that of Oil City, and 50-80 ft. thick. The sp. gr. of the oil ranges from 30° to 32° B. (0.879-0.868), the most productive well giving 150 barrels a day. At Foster, the 3rd sand, 12-14 ft. thick, is struck at 610 ft. ; at Scrub Grass, it is 18-20 ft. thick, at 615 ft.
East Sandy, the connecting link between the Upper and Lower oil-belts, comprises Gas City, where the sand rock was 60 ft. thick, at 850 ft.
The great Lower oil-belt has klength of some 21 miles, beginning at Triangle City (Clarion county) and apparently terminating at St. Joe (Butler county). After leaving Barns City, it splits
into two well-defined beds, known as East and West. The entire width of the belt does not exceed 3 miles, but the productive area is uninterrupted, instead of being in detached spots, as in the Upper belt. The Baud rock dips so rapidly in one section that the wells are there drilled to 1600 ft. An idea of the relative position of the sand rock along the belt from the upper end southward may be gained from the following data :-Turkey City, sand on flat, 20 ft., at 1150 ft.; Ocean Level of Pump Station, Turkey City, at 1179 ft. ; St. Petersburgh, 26 ft., at 1241 ft. ; Blanchard and Siggins' well, 26 ft., at 1063 ft. ; Eddinger farm, 24 ft., at 1150 ft. ; Peter King farm, 23 ft., at 1000 ft.; Casino well, 36 ft., at 1065 ft. ; Murray well, 30 ft., at 1027 ft. ; Bear Creek, 33 ft., at 1170 ft. ; Barns City, at 1230 ft., the 3rd sand, 26 ft., at 1440 ft ., and 4th sand at 1535 ft. ; Modoo wells, 12-15 ft at 1450 ft.; William Moore farm, at 1560 ft.; Armstrong Run, 3rd sand 7i ft , at 1263 ft.; Millerstown, at 1550 ft. ; James M'Cready farm, at 1530 ft.
Between the main belts of sand rock which are the great centres of production, are isolated localities, which have been more or less explored. The most prominent are :-1. Near Lowell, heavy oil at 150 ft., and gas, but no oil, at 900 ft. 2. Slippery Rock Creek, many productive wells, some np to 50 barrels, but not lasting ; oil was heavy. 3. Oil Spring Reservation, surface oil. 4. Well at Limestone, at 1050 ft., gave much gas, and oil of 45° B. (0.806 sp. gr.), at first about 5 barrels a day. 5. Wells on Cow Run, about 450 ft. deep, on main belt of anticlinal in the Ohio region. 6. Wells on Duck Creek are part of same belt. 7. Utica, 7 barrels of heavy oil daily. 8. Leechburg, a gas-well, 1200 ft. deep, supplying fuel to the manufactories. 9. Tarentum, where the salt-wells, 450 ft. deep, have always found more or less petroleum within 350 ft. of the surface ; some produce 8-10 barrels a day, the oil separating by the subsidence of the brine, and imparting no flavour. 10. Hosmer Run, wells found much oil at 500 ft. 11. Edinburg, a 10-barrel well, at 260 ft., heavy oil. 12.13. Meadville, gas-well, 6-ft. sand, at 350 ft., no other sand at 1000 ft.