6 PROFESSOR W. J. SOLLAS. 



surrounded by quicksand containing boulders of coral, and as fast as the sand Vv-as 

 got out, so fast it flowed in and faster. The water pumped down disappeared 

 through the sand, boring and d fortiori reaming was impossible, and the tubes 

 could not be driven owing to the interspersed boulders. Had the tubes been 

 provided with steel driving ends we might have forced them down ; as it was, the 

 effect of driving them was simply to curl in the lower end. Had we been provided 

 with 4-inch tubes we could have made a fresh start, and might have descended 

 another 30 or 40 feet, but even then ultimate success wovdd not have been ensured, for 

 the chance of meeting; atjain and again with intermixed sand and coral remained alwavs 

 open, and every such encounter would have required lining tubes of diminished calibre. 



Baffled in our endeavours, and with no other part of the island offering more hopeful 

 prospects of success, we had no alternative but to abandon the undertaking, and 

 on July 30 were taken from the island in the " Penguin," and returned to Fiji. 

 On landing there we had the mortification to learn that additional apparatus was 

 then on the way to Funafuti, our friends in Sj^dney having with great generosity at 

 once despatched machinery for driving through sand on receipt of a letter I had sent 

 informing them of the failure of our first bore-hole. We had no reason to expect 

 such spontaneous assistance, and even had we been fortunate enougl^ to have remained 

 on the island till the machinery arriv^ed, we probably should not have accomplished 

 the object we had in view, tliough \xe possibly might have carried the borehole down 

 to a depth of about 400 feet. 



A very free communication must have existed between the bore-hole and the sea, 

 for whenever a big roller broke upon the reef the rods lifted, and after tlie lining- 

 had been withdrawn, water spurted out of the l:)ore-hole witli the fall of every 

 wave. The open nature of the reef is further indicated l)y the fact that the sea 

 water rises Avith every tide to fill certain depressions, which occur in many places in 

 the middle of the island ; as the tide ebbs this water flows away down fissures, often 

 so rapidly as to form little whirlj)Ools. 



Wherever I have seen the reef grow ing it has always })resented itself as clumps 

 or islets of coral and other organisms with interspersed patches of sand, and the 

 borings would seem to indicate that it maintains this character for a very consider- 

 able depth, and possibly throughout. The structure of the reef appears indeed to be 

 that of a coarse "sponge" of coral witli wide interstices, which may be either empty 

 or filled with sand. 



As regards tlie nature of this "sand," it is important to observe that it does not 

 consist of coral debris; this material and fragments of shells forming but an 

 insignificant part of it ; calcareous algae are more abundant, but its chief constituents 

 are large foraminifera, which seem to belong chiefly to two genera {Orhitolites and 

 Tinoporus). It covers a considerable area of the islands, and has accumulated 

 during the memory of the inhabitants to such an extent as to silt up certain parts of 

 the lagoon. This and the abundant growth of corals and calcareous algaj, such as 

 Halimeda, lead to the belief that the lagoon is slowly filling up. 



