THE BAHAMA ISLANDS 5 



In about the year 1890 Dr. John I. Northrop spent six months in the 

 Bahama Islands, during which time he visited New Providence and Andros. 

 On his return to the United States he published an account of his observations." 

 This paper is especially interesting from the fact that he believes that the 

 Bahamas are rising. " I think the facts I have given justify my conclusion 

 in regard to the recent elevation of Andros and New Providence. It is probable 

 that the elevation extended over the rest of the Bahamas, as caves exist on the 

 other islands. What the Bahamas are doing to-day, of course, we cannot tell; 

 but until we have proof to the contrary, we may assume that they are rising." ' 



No other work of importance appeared until Prof. Alexander Agassiz 

 published his researches on the Bahamas." The reconnoissance which Agassiz 

 here describes was undertaken during the winter and early spring of 1893. He 

 had at his disposal the steamship Wild Buch, and cruised throughout the entire 

 archipelago. The descriptions of the Bahamas which he gives in the Bulletin 

 are very complete and are the best which have ever been published. As a 

 result of his researches he concluded that the Bahamas had at one time stood 

 higher and were more extensive than at present; that they had subsequently 

 subsided for at least 300 feet; and that during this period their areal extent 

 had been further diminished by erosion. In this connection he says : " After 

 the formation of the islands came an extensive gradual subsidence, which can 

 be estimated at about three hundred feet, and during this subsidence the sea 

 has little by little worn away the seolian hills, leaving only here and there 

 narrow strips of land in the shape of the present islands. . . . Subsidence 

 explains satisfactorily the present configuration of the Bahamas, but teaches us 

 nothing in regard to the substratum upon which the Bahamas were built. In- 

 deed, the present reefs form but an insignificant part of the topography of the 

 islands, and they have taken only a secondary part in filling here and there a 

 bight or a cove with more modern reef rock, thrown up against the shores so 

 as to form coral reef beaches such as we find in the Florida Eeef ." ° Agassiz 

 evidently did not observe any of the raised marine deposits which are discussed 

 . later in this chapter, for he says : " I did not meet anywhere with deposits 



'Notes on the Geology of the Bahamas, Trans. N. Y. Acad. Scl., 1890, vol. x, 

 Oct. 13, pp. 4-23. 



*Loc. cit., p. 22. 



° Observations in the West Indies, Am. Jour. Sci., 1893, vol. xiv, pp. 358-362. A ' 

 Reconnoissance of the Bahamas, etc.. Bull. Mus. Comp. Zool., 1894, vol. xxvi. No. 1, 

 pp. 1-108. 



' Loe. cit., p. 7. 



