NOTES AND QUERIES. 
259 
tions of the pipes have fallen down, giving the patched appearances seen in the 
illustration. I could not trace the pipes lower than the depths given above, 
jwing to their disappearance in the talus and rubbish at the base of the chalk- 
platform, which has been left to support the planks on which the workmen 
wheel the barrows to the lime-kilns. I have preserved a specimen o'f the sandy 
clay taken from the lowest attainable depth in one of the pipes (fig. 1, c), with 
.a flint that was embedded in it. This mass seems to be a mixture of clay from 
4 inches, 
Vegetable mould. 
Angular flint gravel. 
Coloured sands, finely laminated. 
Band of small pebbles. 
White or grey quartzite sands, rather darker 
than those seen at Charlton. 
Band of red oclireous sand and clay containing 
green-coated flints. 
Chalk. 
Fig 2. — Section above the sandpipes, showing the strata through which the water 
percolates. 
No. 6, and sand from the superincumbent strata No. 5 (fig. 2) ; but the white 
grains of the sand are much discoloured by the oxide of iron contained in the clay 
No. 6. The flint is not in the least degree water-worn, but has one of its pro- 
jecting portions broken off, showing the fracture clear and distinct : it is not 
tinged by the red clay which suiTOunded it, and still preserves the outer white 
coating characteristic of chalk-flints. The chalk forming the sides of the 
pipes is invariably disintegrated for about two inches into the solid mass of 
chalk forming a cellular or spongy substance, and may by slight pressure be 
reduced to fine powder. 
The extreme depth and uniform width of these pipes, although frequent 
examples are met with, are not the common characteristics of sandpipes 
occurring in cretaceous stiata, which are generally more or less triangular or 
funnel-shaped (fig. 3), and this led me for the moment to imagine that they might 
be fissures into which the clay and sand had been washed or had fallen ; but the 
stratification of the chalk in their neighbourhood being nearly level and quite 
