part 1] PHOSPHATE DEPOSIT OF OCEAN ISLAND. 3 



methodically the conditions under which the phosphate deposits of 

 the Pacific were formed. The author records several interesting 

 observations. At the time when his paper was written, Ocean 

 Island, as a phosphate deposit, was unknown. 



(2) ' Nature & Origin of Deposits of Phosphate of Lime.' E. A. F. Pen- 

 lose, Jr., Bull. U.S. Geol. Surv. No. 46, vol. vii (1888) p. 475. 



This paper includes a comprehensive account of the then known 

 phosphate deposits of the world. At the time when it was written, 

 the most valuable of the Pacific phosphate deposits had not been 

 discovered. 



(3) ' Phosphate-Deposits of Ocean & Pleasant Islands.' F. Danvers 

 Power, Trans. Austral. Inst. Min. Eng. vol. x (1905) p. 213. 



Taking into consideration the short time that this author spent 

 •on these islands, his account is remarkably comprehensive and 

 accurate. The paper is illustrated by plans and several good 

 photographs, and is a valuable contribution to the subject. With 

 the facts recorded by this author, I am in almost entire agreement; 

 but with his theory of the mode of formation of the present 

 deposit from the original guano I am in almost entire dis- 

 agreement. 



(4) ' Corallogene Phosphat-Inseln Austral- Oceaniens & ihre Produkte.' 

 Carl Elschner, Lubeck, 1913. 



In this book the author has collected data and photographs 

 from various sources, and he is particularly indebted to Mr. Danvers 

 Power's paper. There is little original matter of any value in 

 the book, and very little discrimination has been used in the 

 selection of data. The most valuable part of this work lies in the 

 illustrations, some of which are beautifully reproduced. 



III. General Stettcttjee oe Ocean Island. 



Ocean Island, as it exists at the present day, consists of a mass 

 •of dolomitized coral, almost completely covered by a cap of 

 calcium phosphate, and shaped like a flat dome. It rises at its 

 highest point to 300 feet above sea-level. The circumference of 

 the island is about 6 miles, the coast-line being almost circular, 

 with the exception of the bight known as Home Bay on the 

 south-west. The latitude and longitude of the island have been 

 variously given, the extreme figures differing as much as 14', but 

 lat. 0° 52' S. and long. 169° 32' E. may be taken as very nearly 

 correct, as I have obtained confirmation of these figures from many 

 able navigators who visited the island. 



In all but the southernmost portion, the coast consists of nearly 

 vertical and much eroded cliffs up to 30 feet in height, and 

 seaward extends a platform of marine erosion averaging about 

 100 yards in width. 



As stated above, practically the whole of the island is capped by 

 a deposit of phosphate, sometimes as much as 80 feet thick, but 



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