270 Dr. J. D. Dana on the Origin of 



not than Darwin on the special subject under discussion. 

 The facts from " a widening circle of observations " referred 

 to comprise the physical and biological results of deep-sea 

 exploration. The writer is mentioned as one of the " com- 

 petent observers ,J who had given " independent testimony " 

 in favour of Darwin's views after "at least equal opportunities 

 of studying the subject/' and as he has, in these latter years, 

 looked into the new facts, he has at least a claim to a hearing. 



As to Darwin's knowledge, it appears to the writer that the 

 apology offered in the above citations was not needed. In 

 his detailed investigation of Keeling atoll (a good example 

 of atolls, and like all the rest in its principal features) and 

 in his examination of the Tahitian reefs, followed up by a 

 careful study of other atolls and reefs of the ocean through 

 the maps and descriptions of former surveying-expeditions, 

 he had a broad basis for judgment and right conclusions. 

 When the second edition of his work was published in 1874, 

 many of the important facts from deep-sea exploration were 

 already known ; and later he learned of the more recent 

 results ; and he did not recant. A letter of his, of October 

 2nd, 1879, published by Mr. Semper, while admitting with 

 characteristic fairness the interest of the facts collected by the 

 latter, expresses his continued adherence to the opinion "that 

 the atolls and barrier reefs in the middle of the Pacific and 

 Indian oceans indicate subsidence." 



The writer, as his expositor, may be excused for adding 

 here that his own " independent testimony " was based on 

 observations among coral reefs and islands in the Pacific 

 during parts of three years, 1839, 1840, 1841 ; that, besides 

 working among the reefs of Tahiti, the Samoan (or Navi- 

 gator) Islands, and the Feejees (at this last group staying 

 three months) , he was also at the Hawaian Islands ; and in 

 addition, he landed on and gathered facts from fifteen coral- 

 islands, seven of these in the Paumotu Archipelago, one, 

 Tonga tabu, in the Friendly Group, two, Taputeuea and Apia, 

 in the Gilbert Group, and five others near the equator east of 

 the Gilbert Group — Swains, Fakaafo, Oatafu (Duke of York's), 

 Hull, and Enderbury Island*. The writer may therefore be 

 acquitted of presumption if he states his opinion freely on the 

 various questions that have been brought into the discussion 

 by other investigators. Sympathizing fully with the senti- 

 ment expressed in the words, " The example of Darwin's own 

 candour and over-mastering love of truth remains to assure 



* These five islands are on the map of the Central Pacific accompany- 

 ing Part I. of this paper. Hull's Island is "Sydney" of the writer's Expe- 

 dition Report. 



