THE NONMETALLIC MINERALS. 441 



Well No. 3, farm of Jennings & Ralston, Jackson, Venango County, Pennsylvania. 

 (59774.) 



(8) From just above the third sandstone of the Petroleum Measures (Venango). 

 Sand here 22 feet in thickness; oil in sand; depth of well 1,076 feet, drilled 1885; 

 torpedoed; yielded 18 barrels of oil on first day of pumping. Dark greenish; specific 

 gravity 49 Baume*. Well No. 5, Diamond farm, Cranberry, Venango County, Penn- 

 sylvania. (59795.) 



(9) From the third sandstone of the Petroleum Measures (Venango). Sand 18 

 feet in thickness; oil in sand; depth of well 957 feet; drilled 1885; not torpedoed; 

 yielded 35 barrels of oil on first day of pumping. Black ; specific gravity 48? Baume. 

 Well No. 1, Heckerthorne farm, Cranberry, Venango County, Pennsylvania. (59815. ) 



(10) From the fourth sandstone of the Petroleum Measures. Dark greenish red; 

 specific gravity 44 Baume. Kangaroo well No. 1, East Brady, Clarion County, 

 Pennsylvania. (59489.) 



(11) From the third Bradford sand. Black. Nile Oil Company, Wert, Allegany 

 County, New York. (59477.) 



The following five specimens from various localities continue the 

 section to the lowest point at which petroleum has been found: 



(1) From the Middle Devonian formation. Black. Near Glasgow, Barren County, 

 Kentucky. (59544.) 



(2) From the Corniferous limestone. Black; specific gravity 35.5 Baume. 

 Crown well, Enniskillen, Province of Ontario, Canada. (59569.) 



(3) From the Upper Hudson River shales (Lower Silurian). Dark greenish; 

 specific gravity 43.5 Baum6. Well No. 2, near Glasgow, Barren County, Kentucky. 

 (59599.) 



(4) From the Hudson River group (Lower Silurian). Black; specific gravity 

 32 Baume\ Pioneer well, Francisville, Pulaski County, Indiana. (59575.) 



(5) From the Trenton limestone. Black. Farm of Whitacre, Liberty, Wood 

 County, Ohio. (59601.) 



ASPHALTUM; MINERAL PITCH. These are names given to what are 

 rather indefinite admixtures of various hydrocarbons, in part oxygen- 

 ated and which for the most part solid or at least highly viscous at ordi- 

 nary temperatures, pass by insensible gradations into pittasphalts or 

 mineral tar and these in turn into the petroleums. They are charac- 

 terized by a black or brownish-black color, pitchy luster, and bitumi- 

 nous odor. The solid forms melt ordinarily at a temperature of from 

 90 to 100 F., and burn readily with a bright flame, giving off dense 

 fumes of a tarry odor. The fluidal varieties become solid on exposure 

 to the atmosphere, owing to evaporation of the more volatile portions. 



The nature of the material, its mode of occurrence, and indeed the 

 uses to which it can be put vary to such an extent with each individual 

 occurrence that a few only of what are the most noted or best known 

 can here be mentioned. 



On the island of Trinidad is an immense superficial deposit having 

 an area of about 114 acres and a depth varying from 18 to 78 feet. 

 The surface is nearly level and of a brownish-black color. (See Speci- 

 mens Nos. 68063, 68065, 68066, U.S.N.M.) 



The deposit has in numerous publications been compared to a lake 



