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The Building of an Island, being a Sketch of the Geological 



Structure of the Danish West Indian Island of St. Croix, or 



Santa Cruz. By John T. Quin. F.R.G.S. The Author, Christiansted, 



St. Croix. igo7. 4to. 



The twelfth or concluding chapter of the work under consideration begins as 



follows: 



While it seems desirable, in entering on the study of the geological formations of our island, to 

 betcin with the younger set of rocks and trace the story backwards, it may be instructive, in suramar- 

 izin:; the results of our observations, to take the opposite course, and, as far as possible, note leading 

 even Is and conditions in their natural sequence. 



As a preliminary, we must remember that the crystalline structure prevalent in our older forma- 

 tion has I, -n induced in the strata since the materials of which they are composed were deposited, and 

 similarly that the dikes of igneous rock which we find cutting them through have been intruded so that 

 in the first instance we have to confine our thoughts simply to their deposition. 



While th.iiil<ing the author for the valuable suggestion that the components 

 of a rock were on hand when and where that rock was formed, we, and prob- 

 ably a great many others, had been bold enough to suppose this fact without first 

 consulting him. He is manifestly a schoolmaster, or, as modern American termi- 

 nology has it, an "educator," and he attempts in twelve dismal chapters and with 

 the aid of diagrams and plans, together with a map as recent as 1856, to "edu- 

 cate" us to a vague conception of the building or formation of the island of St. 

 Croix in the Danish West Indies. The above quotation gives an idea of his 

 average style, but we shall not attempt to give specimens of the pedantry dis- 

 played in almost every part of the book. It is diificult to conceive whether that 

 book is written for a well-informed public or for a primary school. If for the 

 former, the childish object lessons, as in the first chapter, the tiresome and almost 

 offensive explanation of the cause why lime-rock effervesces in muriatic acid and 

 clay does not, the interesting statement that soils are classed among rocks, and 

 the almost endless dissertation on Foraminiferae and the like are wholly super- 

 fluous; if for children, the bulk of the text has too many pretensions to being 

 technical. 



We look in vain for terse, logical conclusions. All we can discern is, that the 

 author favours the opinion that there may have been two successive formations of 

 the island, one, possibly anterior of the Cretaceous period and followed by sub- 

 mersion; then again, slow upheavals and subsequent deposits so as to form an- 

 other dry surface. The latter "perhaps" at the time of the chalk formation. Trap 

 dikes indicate that the volcanic forces have, to a limited extent, risen to the de- 

 gree of eruption on the surface. We do not attempt to penetrate any further 

 into the intricacies of the book, wishing the reader much patience in his endea- 

 vours to peruse it. The illustrations are mostly quite commendable. A. F. B. 



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