54 PEOFESSOR T. W. EDGEWORTH DAVID. 



1st. The depth for which Darwin had asked that a coral atoll should l)e bored 

 with a view to testing his theory (500-600 feet) had l)een exceeded l)y reaching 

 698 feet, and a core had been obtained as good as could be expected considering 

 the' friable and fragmental character of much of the rock. This was carefully 

 labelled and forwarded early in 1698 to the Royal College of Science, London, 

 for slicing and for chemical and microscopic examination. This core proved that the 

 atoll was formed, from the surface to the bottom of the bore, of calcareous rock chieHy 

 composed of foraminifera, Lithothamnio)} , and Halimeda, as weW as of reef-forming 

 corals. The lower part of the core a])peared j^articularly interesting and important. 

 At first sight it seemed like a consolidated chalky ooze, and our first impression was 

 that it represented the beginning of the original foundation of the coral atoll. Later 

 examination in the laboratories at the Royal College of Science, London (for the 

 results of which see Sections XIL and XIV.), and at Sydney University, showed 

 that this rock was laro-elv coral-reef material converted into dolomite. It was 

 evident then, that the base of the coral-reef rock had not yet been attained. 



2ud. Geological surveys had l)een made of tlie various islets of tlie atoll, in 

 sufficient detail to admit of maps being constructed from them, which it was hoped 

 woidd be^ of use later in the study of any changes which the islets might subsequently 

 undergo, as well as in supplying information as to the latest geological histoiy of the 

 atoll. These maps are published with the present vohnne (Plates 1-19). 



3rd. A collection had been made of the various organisms living on the seaward 

 slope of the atoll, from depths of between 20 fathoms and 200 fathoms. Tliese, 

 together with a few samples of the floor of the lagoon, secured by means of a sand- 

 puni]), had also been forwarded to tlie Royal College of Science, London. It was 

 hoped that this collection might prove of use for comjjarison with the dead organisms 

 in tlie cores from tlie diamond-drill bores. 



In view of the fact that much of the drill machinerv had l)een left at the atoll 

 as well as a supply of coal, and that it was expected that there would be no 

 difficulty in washing out the silt from the old bore, it was considered ^ery desirable 

 that an attempt should be made to deepen the main bore, and accordingly the 

 Government of New South Wales and the Royal Society of London were approached 

 on this subject. They both generously responded, tlie former again placing a 

 diamond drill at the disposal of the scientific party and agreeing to bear a portion 

 of the cost of the borinp', while the latter contrilmted handsomely in funds. 

 Mr. A. E. FiNCKH volunteered to go as leader of this, the Third Expedition to 

 Funafuti, and the difficulty of transport to the atoll was again got over through the 

 kindness of the London Missionary Society in undertaking to convey gratuitously the 

 diamond-drill party and gear, as well as a further supjjly of coal, from Samoa to 

 Funafuti. 



Meanwhile information was sent to Sydney by Captain Creak, R.N., F.R.S.,* that 



* See Section III, p;ige .3G. 



