PITCH LAKE OF TRINIDAD. 185 



The most abundant petroleum springs known are 

 those on the river Irawadi, in the Birman Empire; 

 there being 520 wells in one locality, which yield an- 

 nually 400,000 hogsheads of petroleum. 



Fluid bitumen oozes from the bottom of the sea, 

 on both sides of the Island of Trinidad, and rises up 

 to the surface of the water. According to Dr. Hol- 

 lend, the petroleum springs of Zante are much in • 

 the same state as in the tiine of Herodotus. The 

 principal pool is about 50 feet in circumference, and 

 a few feet deep ; the sides and bottom of this and 

 the others are thickly covered with petroleum, which, 

 by agitation, is brought to the surface of the water, 

 and collected. The amount obtained is about 100 

 barrels annually. 



The pitch lake of Trinidad is about three miles in 

 circumference. The asphaltum is sufficiently hard 

 in wet weather to support heavy weights, but during 

 warm weather it is nearly fluid. It is intersected 

 with numerous cracks filled with water, which some- 

 times close up, leaving marks on the surface. When 

 highly covered with soil, as it is in many places, good 

 crops of tropical productions are obtained ; but, ow- 

 ing to this covering of soil, it is said to be difficult 

 to ascertain the boundaries of the lake. Large quan- 

 tities of naptha are obtained on the shores of the 

 Caspian. The inhabitants of the town of Badbree, 

 a port on that sea, are supplied with no other fuel 

 than that obtained from the naptha and petroleum, 

 wiih which the adjacent country abounds. The nap- 

 tha springs at Rangoon, Pegu, produce over 92,000 

 tons per annum. Mr. Lyell supposes that bitumi- 

 nous minerals are produced from vegetable substan- 

 ces which have undergone certain transformations 

 and chemical changes by the agency of subterra- 

 neous fire. ''The bituminous shales," he remarks, 

 "so common in geological formations of different 

 ages, as also many stratified deposites of bitumen 

 and pitch, seem clearly to attest that, at former pe- 



