BY T. STEPHENS, M.A., F.G.S. 95 



"built up on tops of submarine peaks or ridges already existino^ 

 at a depth not exceeding 25 fatlioms, or on banks which, in 

 the course of ages, had been raised to the necessai'y heio-ht 

 Tdj the process of sedimentation that has been described. 

 (Reference to diagram.) 



In a letter quoted by Professor Judd, which was written 

 by Darwin to Professor Agassiz in 1881, the year before his 

 death, he remarks that he " has expressly stated that a bank 

 at the proper dej^th would give rise to an atoll, which could 

 not be distinguished from one formed during subsidence ; " 

 and he goes on to say that he " can hardly believe in the 

 existence of as many banks (there having been no subsidence) 

 as thei-e are atolls in the great oceans, within a reasonable 

 depth, on which minute oceanic organisms could have 

 a^ccumulated to the depth of many hundred feet." The letter 

 concludes with the following words : — "If I am wrong, the 

 sooner I am knocked on the head and annihilated so much 

 the better. It still seems to me a marvellous thing that there 

 should not have been much and long-contiuued subsidence in 

 the beds of the great oceans. I wish some doubly-rich 

 millionaire would take it into his head to have borings made 

 in some of the Pacific and Indian atolls, and bring home 

 cores for slicing from a depth of 500 or 600 feet." 



The " millionaire " did not turn up, but Darwin's last 

 "wishes for the settlement of the question one way or another 

 were not consigned to oblivion, and at last, in 1896, the 

 Royal Society of London organised an expedition under the 

 leadership of Professor Sollas, Avhich was materially aided 

 by the Admiralty, the Government of New South Wales, and 

 leading scientific men in Sydney. A site was selected for 

 boring operations in the EUice Group, due north of Fiji, and 

 about 8deg. south of the Equator. A lagoon encircled by a 

 fringe of reefs and coral islands, the largest being Funafuti, 

 forms the atoll, which is about 12 miles long and eight miles 

 broad. From soundings taken by Captain Field, ot H.M.S. 

 Penguin, it appears that this atoll resembles a vast wall-like 

 structure built on a cone-shaped elevation or mountain rising 

 from a depth of about 2,000 fathoms, with a gradually 

 increasing slope up to a contour line about IrlO fathoms deep, 

 the rise from this level up to near the surface being almost 

 precipitous. The intention was to bore to a depth of at 

 least 600 feet, so as to ascertain how far down the coral reef 

 extended, and to determine, if possible, the nature of the 

 foundation on which it rested. The boring was commenced 

 in May, 1896, but was carried on under great difficulties, the 

 tubes constantly getting choked by sand lying in irregular 

 layers among masses of solid coral. A depth of 105 feet 

 was reached, but eventually the work had to be abandoned. 



