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Guppy Reprint 



171 



earth movements, and in my paper on the "geological connexions 

 of the Caribean Region" I indicated on a map what I conceived 

 to be the course of the principal dislocations, the most evident of 

 which I have called the 1 'great antillian dislocation." I exhibit 

 this map to you now. In the early part of 19 10 I visited Antigua 

 and other islands with a view to extending my acquaintance with 

 the geology of these Islands. In previous years I had explored 

 several of the islands, particular^* Dominica, St. Vincent and 



Page 2 j 



Grenada. In spite of my physical disqualifications I was enabled 

 to discover some very important facts and to make these known I 

 drew up a paper which was read to the Geological Society of 

 London on the 24th May last. I exhibit copy of the paper and 

 will briefly explain its purport. 



Before my visit to Antigua I was under the impression that 

 the volcanic rocks of that island belonged to a different period 

 and that the great antillian dislocation did not pass through it 

 but to the west and south of it. There was nothing in the writ- 

 ings of the authors who had previously written of Antigua to 

 lead me to doubt this view. 



After noticing the work of former observers on the geology 

 of Antigua, I gave a brief description of the formations of that 

 island, showing that it is divided into three principal regions — 

 (1) the Volcanic (or Igneous) Region ; (2) the Central Plain ; 

 and (3) the Calcareous Formation, the first-named being, accord- 

 ing to previous authors, the oldest, as it is pre- tertiary, and the 

 others following in succession. The calcareous formation, hith- 

 erto considered the newest, contains fossils, of which the most 

 remarkable is a species of Orbitoides. After a discussion of these 

 formations and especially of the evidence for the so-called 'Oli- 

 gocene' age of the calcareous formation, the conclusion is reached 

 that this formation is the oldest — not the youngest, and is 

 probably Eocene or older. The island was raised above sea-level 

 by the development of the great antillian dislocation, which di- 

 vides each of the islands of Guadelupe and Antigua into two parts, 

 of which the eastern is calcareous and the western volcanic. In 



