20 



THE POPULAR SCIENCE MONTHLY 



Photo, C. R. Toothaker, Phila. Commercial Museum. 

 Trinidad Pitch Lake. 



The shape and structure of the long promontories which have been 

 mentioned reveal the fact that Trinidad is, structurally, intimately con- 

 nected with the mainland. This is proved by the geology and fauna 

 of the island, the latter corresponding closely to that of the mainland 

 and the geological structure being a continuation of that of the conti- 

 nent. Its climate is entirely tropical and somewhat different from that 

 X)f the remaining Antilles in this respect. 



Trinidad was discovered by Columbus on his third voyage in 1498 

 "and taken possession of in the name of Spain, which colonized it about 

 ninety years after. In 1797 it was taken by Great Britain, and has 

 remained since then one of her most important West Indian colonies, 

 and the second in size. 



The Island of Trinidad, while not directly connected with the chain 

 of islands of volcanic origin known as the Windward or Caribbean 

 Islands, is directly on the great line of volcanic disturbances running 

 from these to the continent of South America and its volcanic regions. 

 Many cf the Windward Islands are still possessed of active vents, so that 

 Trinidad may be looked upon, with its thermal springs and pitch 

 deposits, as being situated at the lowest point between the mountainous 

 volcanic chains of the West Indies and those of South America. More 

 than two thirds of the surface is of Tertiary or recent origin, including 

 the entire southern portion, where the pitch deposits are located. The 

 formations consist of clay, loose sand, shales, limestones, calcareous 

 sandstones, indurated clays, porcelainites of brilliant colors, with pitch 

 deposits here and there. The beds have been considerably disturbed and 

 have at times a large dip. In a series of sands, clays and shales lies the 

 pitch lake. 



While there are deposits of pitch scattered all over the island, the 

 only ones of commercial importance are those situated on La Brea Point, 



