CRUISE OF THE PORPOISE. 287 



that we should find but little coral sand, and an occasional stratum of 

 coral rock. Since my return, I have seen the results of a .similar 

 experiment, made by Captain Belcher, on another island, (Hau or 

 Bow Island,) in the same group. They are identical with ours. 



Before I close the subject of coral islands, I cannot refrain from 

 making a few remarks, derived from my own observations while I 

 was engaged among them. My opportunities have been numerous, 

 and I have had every facility for viewing to advantage, not only those 

 exclusively of coral formation, but also the reefs that surround the 

 high volcanic islands, which afford the most safe and convenient 

 harbours of the Pacific. 



After much inquiry and close examination, I was unable to believe 

 that these great formations are or can possibly be the work of zoo- 

 phytes ; and the arguments by which it is endeavoured to maintain 

 this theory, appear to me to be inconsistent with the facts. I cannot 

 but view the labours of these animals as wholly inadequate to pro- 

 duce the effects which I observed, and I was satisfied that the very 

 appearance of the reefs was sufficient to contradict any such impres- 

 sion. The ingenious theory of Darwin, which has of late been 

 promulgated, and which holds that an equal subsidence and growth 

 are taking place, is alike at variance with the configuration, extent, 

 and general construction of the reefs. 



In all the reefs and islands of coral that I have examined, there are 

 unequivocal signs that they are undergoing dissolution. Thus, it 

 will be recollected, that in the first volume of this narrative, I gave 

 various sketches of coral blocks now existing on the top of reefs, and 

 also spoke of the various shelfs, soundings, and longitudinal cracks 

 that I had observed. All these phenomena have been since those 

 first observations repeatedly met with. To account for the position 

 of these blocks, it has been assumed that they had been thrown up 

 by the sea; but their positions, weight, and situation, are such as to 

 contradict such an idea. They are found in many cases standing erect 

 on their smaller ends, and have evidently formed an upper shelf, of 

 which they are now the sole remains. In every observed instance, 

 they were at some distance from the outer edge of the reef on which 

 they stand, and they were also seen covered with debris of the coral, 

 that has been mentioned as forming the higliest portion of the islands. 

 It would be utterly impossible for any sea to toss so great a weight 

 to such a distance ; and if such masses were even broken off from a 

 reef by the action of water, they would undoubtedly have obeyed 



