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•character ; (b) sharp, clean fractures; (c) its occurrence in loose 

 sand ; (d) absence of an}^ local geological evidence of rocks of 

 this type. 



2, The evidence, so far as it goes, points in the direction that 

 these fragments have been introduced into the locality in com- 

 paratively recent times. Recently formed surface limestone and 

 sand rock are extensively developed in the neighborhood, and 

 rise into cliffs one hundred feet high. These rocks in consoli- 

 dating have caught up into their mass whatever surface material 

 may have been at hand. Had the bituminous matter originated 

 in the locality it seems highly probable that some evidence of its 

 occurrence would have been shown in these recent superficial 

 beds. Although carefully looked for, not a vestige of such could 

 be found. The inference is that the bituminous material has 

 been introduced into the locality subsequently to the formation 

 of these recently consolidated beds, or that it exists locally in 

 very limited quantities. 



In conclusion, three explanations may be considered in 

 accounting for this occurrence over so great a length of sea- 

 board. 



1. That the bituminous material has been derived from a 

 natubval bed locally developed. Whilst not impossible such a 

 view we regard as highly improbable. No visible rock in the 

 district is at all likely to produce bituminous material, which can 

 only be derived from the decomposition of organic matter, the 

 existence of which in the local rocks there is not the slightest 

 evidence. If it has a natural and local origin it is almost 

 certainly sub-marine, and most likely of Tertiary age. Beds of 

 this age have been already referred to as outcropping on the 

 Island, but in both the localities mentioned their base is exposed, 

 the one resting on glacial clay, and the other on granite, without 

 the slightest indication of bituminous material. Moreover, had 

 the asphaltum oozed out beneath the sea the material would 

 certainly have become mixed with a good deal of foreign matter, 

 whilst the specimens found are very uniform and pure. 



It is worth remarking that in Cuba submarine beds of asphal- 

 tum are worked at four different localities. The beds are con- 

 tained in rocks of Lower Eocene age, and have been mined in 

 water from 80 to 125 feet in depth for the past 25 years. One 

 of these deposits, situated in Cardenas Bay, is of unusual rich- 

 ness, and is described in its appearance as resembling cannel coal 

 with a more brilliant lustre. Whilst the geological evidence is 

 decidedly unfavorable, the peculiar conditions under which 

 mineral oil is sometimes found imposes on us a measure of caution 

 in athrming that it is impossible to occur on our shores as a 

 natural product. 



