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manner at different sides of the shaft. The ground below 
appeared to be loose and disturbed, as was shown by the ease 
with which an iron rod could be thrust downwards to its full 
length of 8 feet, compared with the variable but always much 
greater difficulty attending a horizontal thrust. At the depth 
of 42 feet, the timber framework of the lower shaft began to 
settle down on one side very markedly. This settlement was 
down to the north and north-west, the southern side resting 
apparently on more solid ground. As the funds at the service 
of the Subsidence committee were getting very low, and further 
excavation promised to be a work of great expense if not of 
danger, it was resolved to cease digging and to try the follow- 
ing plan, which was proposed by Mr. Bond, one of the most 
active and useful members of the committee. 
Gas-pipes, with an internal diameter of 1-| in., were screwed 
together and driven down vertically from the bottom of the 
shaft. All solid matter was kept out of these pipes during 
their descent by means of a plug with a harpoon-like point, 
which fitted into the lowest end ; the base of this point was of 
somewhat greater breadth than the external diameter of the 
pipes. Having reached a depth of 85 feet from the surface, 
the pipe was raised a few inches and the plug dropped out ; 
then a slender rod, with a kind of spoon at its lower end, was 
passed down the pipe, and a spoonful of the stuff just outside 
its lower end brought to the surface. As the pipe was with- 
drawn, spoonfuls were brought up at intervals of a few inches, 
so that samples of the material just outside the pipe at various 
depths between 42 and 85 feet were obtained. Both on driving 
clown and withdrawing the pipe, the resistance encountered 
varied exceedingly, a progress of 13 feet in one day being 
followed by one of as many inches the next. Yet there was 
but little variation in the nature of the material extracted ; and 
it seems likely that the occasional presence of hard nodules, 
such as may be sometimes found below the well-known shell 
beds of the Woolwich series, was the cause of the occasional 
slow progress. 
The stuff brought up in the spoon was, between 42 and 50 
feet or thereabouts, brown or greenish-brown sand, with but 
little clay, and occasionally a small pebble. Below 50 feet, no 
pebbles were brought up, and the proportion of clay to sand 
increased with the depth, though not with perfect regularity ; 
so, also, did the proportion of dark blue clay to brown. No 
fragments of shells could anywhere be detected. 
It will be well now to consider what evidence we have of 
the thickness and character of the various beds at Blackheath, 
and the bearing of this evidence on the results of our explora- 
tion. At the house next to the Sun-in-Sands, Shooter’s Hiil 
