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BuixETin 35 



330 



One of these was whether the volcanic rocks underlay the cal- 

 careous formation. I found no evidence that they did, though 



Page 2 



the}^ [it] may be admitted that it is ver}^ difficult to find anything 

 like a satisfactory exposure of the junction of the rocks. I ar- 

 rived at the conclusion that the volcanic rocks do not pass under 

 the calcareous formation. In this conclusion I am supported 05^ 

 Professor Harrison, who also agrees with me on the second point 

 of my inquiry, which was as to whether the volcanic series had 

 undergone submergence and re-elevation. It is probable that 

 the sea at one time overflowed the central plain for it has left 

 marine deposits and other marks of its sojourn there. But that 

 it ever covered the volcanic hills since their formation is highly 

 improbable, Meteoric water in cutting out and enlarging the 

 ravines and denuding the slopes has no doubt given to the mater- 

 ials re-deposited by it the character of alluvial or sedimentary de- 

 posits, but this scarcely affects the general facts. When in Eng- 

 land I submitted my rock specimens to Mr. Prior, Mineralogist 

 of the British Natural History Museum, and he was good 

 enough to supply me with the following remarks : "One speci- 

 men no doubt comes from a lava-flow, the others are andesitic 

 tuffs such as are described in Purves' paper." The specimen he 

 decides to be from a lava-flow came from a bed on the central 

 plain. The andesitic tuffs are varied in appearance, but as Mr. 

 Prior pointed out to me their origin from fragmentary matter 

 can easily be detected. The central plain has been the scene of 

 the most varied volcanic phenomena, including those of hot 

 springs and lakes and of eruptions of lava and ejections of mat- 

 ter from Drewhill and other volcanic vents. Not only does the 

 central-plain contain volcanic accumulations and tuffs but it also 

 contains disrupted fragments and outliers of the calcareous form- 

 ation and deposits from lakes and hot springs. I have already 

 pointed out that the calcareous formation of Antigua is not a 

 fragment of land, but a fragment of a marine formation devoid 

 of the debris of land. No remains of any such formation are 

 found on the volcanic islands of the Antilles at a greater height 

 than 300 feet. Up to that height local marine deposits are found 



