374 
NATURE 
[FEeBRuaARY 18, 1897 
abandon this borehole, and to recommence operations on 
another site, if possible in solid rock. 
The structure of the ground passed through in the abandoned 
borehole was'as follows (Fig. 1) :— 
@| Sand with some coral blocks. 
F@ 
3276. 9/723 
Coral reefs and blocks with 
some sand. 
Sand with sore coral blocks. 
a... 
1054. itn 
Fic 1.—Section of the abandoned borehole. 
| labour, at a cost of about £10. 
Although I knew of many places where solid rock forms the 
surface of the ground, it was very difficult to find one to which 
we could transport our machinery ; the difficulties of landing on | 
a rocky shore rendered several promising spots inaccessible by 
sea, while the absence of wheeled vehicles or even wheels, and 
the nature of the ground, seemed to put transportation by land 
out of the question. 
At last, however, Mr. Hedley pointed out to me a portage 
called Luamanif, and used by the natives for dragging their 
canoes from the lagoon to the seaward side of the island, which 
at this place is very narrow, about 70 yards across. As this 
seemed a good landing-place I submitted it to the consideration 
of Captain Field, who, after a personal examination, agreed that 
we might safely make use of it. Ayles and his party were then 
set to work to sink trial-pits on the line of the portage; one of 
these, situated 70 feet from the high-water mark on the seaward | 
face of the reef, was sunk 12 feet through sand and blocks of | 
coral, when operations were brought to a close owing to the 
influx of sea-water at high tides. Two other pits were then 
commenced nearer the sea and a little to one side (north) of the 
portage, at the margin of the solid platform of rock, which 
extends down to the growing edge of the reef, and which is 
covered by the sea at high water. These passed through sand 
and fragments of coral. In the most northern of the two pits 
the sand was somewhat consolidated, and so, proceeding a few | 
yards further north, as far in that direction as it would have | 
been possible to transport our machinery, we opened another 
pit, which was sunk for a depth of 11 feet through fragments of | 
coral, crystalline coral limestone, and partly consolidated sand. | 
The bottom of the pit was 2 feet below the 
seaward margin of the reef, and as we 
were not inconvenienced by an influx of 
sea-water, and Ayles was of opinion that 
the rock would ‘‘stand,” we decided to 
make our new venture at this spot (Fig. 2). 
Taking into consideration the difficulties 
of transporting our apparatus, I do not 
think a more favourable locality could 
have been chosen; it was close to the 
very edge of the rocky platform, which is so hard that 
Darwin, speaking of a similar platform in the case of another 
reef, says, ‘‘I could with difficulty, and only by the aid of 
a chisel, procure chips of rock from its surface”; and as near 
the sea as it was prudent, or even possible, to go. Indeed, we 
NO. 1425, VOL. 55] 
| mittee had considered it would have been completed. 
had at first some doubt as to whether our pumping pipes would 
“live” in the surf of the ocean margin, and feared that the high- 
| water spring tides might inundate the shaft ; our fears in these 
respects, however, proved to be groundless. 
Captain Field and myself were impressed with the need of 
additional boring apparatus, and he proposed that Ayles should 
go to Sydney to see if it could be procured. I gave much 
| anxious consideration to this project, and discussed it with my 
colleagues, Messrs. Hedley and Gardiner, and with Ayles. The 
information I received from Ayles was not encouraging. He 
stated that we should require a complete equipment of lining 
tubes, from 10 inches down to 23 inches in diameter, that 
10-inch tubes were not to be had in Sydney, and that even if we 
succeeded in obtaining all the appliances we required, the 
success of the boring would even then by no means be assured. 
For a doubtful result I did not feel justified in incurring the 
certain increase in our expenditure which a journey to Sydney 
would have involved ; the question of time had also to be con- 
sidered, for had Ayles gone to Sydney we should on his return 
have been commencing our boring at or after the date the Com- 
Finally, 
it appeared that the new locality we had chosen for our work 
offered fair prospects of success. 
The shaft already sunk to a depth of 11 feet was then 
timbered with Pandanus logs, and arrangements made for carry- 
ing down a hole by jumping with a 6-inch chisel. Ayles spoke 
of getting as far as 50 feet by this means, and then lining the 
hole with 6-inch tubes, but after sinking 4 feet he declared 
it impossible to proceed further in this way; the chisel could not 
be made to continue sinking in a straight line, the labour was 
too exhausting, and progress very slow. It was decided, there- 
fore, to begin boring, Ayles being very hopeful, as the hole 
“stood” well. On Thursday, June 25, we accordingly made 
| arrangements to shift our boring gear to the new site, and by 
Saturday, June 27, this work was completed, chiefly by native 
The boilers were rolled along 
the beach, the rest of the machinery taken by water, and all 
subsequently dragged, rolled, or carried across the portage. 
Lieut. Waugh lent us valuable assistance, during the absence of 
the Penguzn, in this work. 
Boring was commenced on Friday, July 3, and by 5 o'clock 
we had sunk another 4 feet ; progress then became rapid, and on 
Saturday evening, when work was knocked off, we had descended 
in all 46 feet. Very little ‘‘ core” was obtained, however, and 
at times the boring bit met with very little opposition as it 
advanced, seemingly passing through a vacant space. Since 
the water pumped into the hole no longer flowed out above, but 
| found its way out by some communication with the sea below, 
it was impossible to determine whether or not some sand might 
have been present. It was clear, however, that the coral rock 
through which the ‘‘ bit” advanced was highly cavernous. 
On Monday the hole became filled with fallen fragments and 
some sand; it was evident, therefore, that the sides would not 
hold, and so recourse was had to lining ; by Thursday, July 9, the 
hole had been reamed and lined down to 45 feet, and the work 
of boring was resumed. On pumping, we had the satisfaction of 
seeing the water flowing out of the top of the hole; but our joy 
was short-lived, for, on Monday, June 13, the water was again 
lost. On Tuesday, July 14, we had reached 65 feet, passing for 
the last 20 feet through sand and coral. Subsequently we 
attained a depth of 72 feet, and could then proceed no further. 
We worked all Thursday and Friday with the sand pump, but 
with no success; the bottom of the hole was surrounded by » 
quicksand containing boulders of coral, and as fast as the sand 
was got out, so fast it flowed in and faster. The water pumped 
Trial pil 7 
Site of Boring 
Bi 
Fic. 2: 
down disappeared through the sand, boring and a fortzorz,. 
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 
