BIT UMEN, A SPHA L T UM, PETR OLE UM, ETC. 221 



very much resembles it, and is used for similar purposes. It occupies a 

 vertical crevice of four to four and one-half feet wide, occurring in the 

 barren coal measures, above the horizon of the Pittsburgh coal. It has 

 been worked, vertically, for three hundred feet and, horizontally, for 3,315 

 feet. The direction of vein is 12° north of west. It was undoubtedly first 

 deposited in a liquid state, subsequently hardening. An analysis by Prof. 

 Wurtz gives specific gravity, 1.145; carbon, 76.45; hydrogen, 7.83; oxygen, 

 13.146; ash, 2.26.* 



MEXICO. 



In the eastern part of Mexico, north of Yera Cruz, bituminous rocks 

 occur, and some coralline limestones are thoroughly saturated with it. An 

 asphaltum also abounds, Avhich Prof. J. P. Kimball likens to G-rahamite. 



PERU. 



At Caxitamba is a small pitch lake, the bitumen from which is found 

 useful in stopping leaks of boats. 



ARGENTINE REPUBLIC. 



Liquid Bitumen occurs in large quantities. Kerosene oil is made of it. 



CUBA. 



There were several fine exhibits of asi^haltum from Cuba in the Spanish 

 section at the Centennial. The bitumen yields one hundred to one hun- 

 dred and forty gallons of oil to the ton, and when purified is admirably 

 adapted for lamps. Daddow and Bannon say that the chapapote or as- 

 phalt is mined, like coal, occurring in fissures in the rocks ;f and flowing 

 springs of petroleum are said to still exist in the vicinity, emanating from 

 fissures extending to the underlying metamorphic rocks. The rocks of the 

 whole island seem to be impregnated with bitumen, and there are numer- 

 ous petroleum springs. 



ISLAND OF TRINIDAD. 



The wonderful Lake of La Braye, according to Parkinson, is one and a 

 half miles in circuit, is hot at the centre but solid and cold towards the 

 shore. Its borders, for a breadth of three-quarters of a mile, are covered 

 with hardened pitch, on which trees flourish. At Point La Braye, the 

 masses of pitch look like black rocks among the foliage, or as black vitri- 

 fied rocks.]: The lake is partly surrounded by mangrove swamps, except- 

 ing towards the sea, and Avhat is remarkable, the lake itself is on higher 

 ground than the neighboring swamps. Its outer margin is solid asphaltum, 

 but further inwards the bitumen, of the consistency of thin mortar, is seen 

 flowing, but in time hardens, and this outward flowing gradually encroaches 

 on the harbor. The outer walls can be cut with an ax, and in appearance 

 resemble an impure cannel coal, but are more gray. On some parts of the 

 surface are seen thin pieces of black, shining asphaltum-. 



*W. D. Fontain, in American Journal of Science, December, 1873. tiron, Coal and 

 Oil — Daddow and Bannon. J Organic Remains of a Former Woi'ld. — Parkinson. 



