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The Ottawa Naturalist [August 



much as $75 to $90 per ton in the EngUsh market. It will be 

 seen, therefore, that this mineral has a high economic value, and 

 with the increase in the demand should form a very im.portant 

 article of commerce. The alhertite of New Brunswick, of which 

 some 250,000 tons were mined before the vein matter was 

 exhausted, was used largely for mixing with ordinary bituminous 

 coals in the manufacture of gas, possessing the property of 

 keeping the production at a high standard. 



It can be readily seen, therefore, that the island of Trinidad 

 possesses great resources in the matter of asphalt, manjak and 

 petroleum, which are now coming into prominence and will 

 undoubtedly, in a few years, become a great source of wealth to 

 the investors and of revenue to the government, since the develop- 

 ment work already done is m-ost encouraging. 



The crystalline schists of the northern range are also well 

 worthy of careful exploitation. The indications of gold in the 

 numerous quartz veins already observed, and of iron ores of 

 several kinds are important, but so far but little attention has 

 been directed to this formation. Nowhere in this island was any 

 indication of volcanic rocks observed either in loose pieces or in 

 actual outcrops. 



In Barbados the geological formations are somewhat 

 different. Of the 166 square miles in the area, six-sevenths are 

 occupied by coral limestone, which doubtless at some time 

 formed a complete capping over the whole island. This coral 

 formation reached to the highest points of the island, or about 

 1,100 feet above the sea, though to the ordinary ob.server or 

 visitor the island is usually regarded as of but small elevation. 

 The remaining seventh in the north-eastern portion shews a series 

 of Tertiary sediments which are almost identical with those seen 

 in Trinidad, and like that island, contain petroleum, and manjak in 

 large quantities. They have been exposed by the denudation 

 of the overlving coral, which presents bold escarpments facing to 

 the east. Between the Tertiary rocks and the coral is a consider- 

 able thickness of earths and clay deposits with an aggregate 

 thickness of nearly 300 feet, which, with the overlying coral 

 formation, are quite undisturbed. 



The Tertiary oil-bearing sandstone and shale are more highly 

 disturbed than those of Trinidad, the anticlines being sharper and 

 the strata in places overturned for short distances. As in 

 Trinidad, boring for oil has been carried on for some years as 

 well as mining for manjak, and some fifteen holes have been sunk, 

 several of which have been carried to depths of over 1,000 feet. 

 In most of these oil has been found in some quantity and a pipe- 

 line and refinery were erected several years ago, the oil being 



