SO.MK KSSEX WKLI.-SECTIONS. 



57 



found that this was closing round the hning-tubc, so that it could 

 not he driven further ; a timbered shaft, 4 feet square, was then made 

 round the tube to the depth of 386 feet. 



The Chalk was so soft, for a great depth, that the tulje had to be 

 carried down to the depth of 844 feet. 



A\'ater was met with at the base of the London Clay, at 434 feet 

 (September, 1887), and still more at 456 feet, when it gave much 

 trouble and was ditificult to keep down, the water rising to 39 feet below 

 the ground. While boring between 844 and 896 feet water began to 

 rise rapidly, to 41 feet from the surface (October, 1888), but on 

 testing the yield the well was pumped dry in 6| hours and took 

 several days to fill again. After further boring the water continued 

 to rise, and at 916 feet stood 23 feet from the surface (November 7, 

 1 888), but a second pumping-test gave no better result than the first. 

 After this the water-level fell somewhat, to 41 feet on July 2, 1889, 

 at 1,048 feet. 



At 473 feet sand blew 200 feet up the tube, and at 476 feet it 

 filled 100 feet of the tube. Since leaving the bottom of the tube it 

 has come in occasionally. 



Thickness. Depth. 



Soil 3 ... 3 



,' Brown sand and gravel 



[River Drift, ' 

 51 feet.] \ 



23 

 38 



Brick-earth '. 12 



Stiff clay (light brown at 32) 15 



Sand, with water (clayey sand at 42) ... 10 ... 48 



Ballast (gravel, of f^int pebbles and flints) 6 ... 54 

 London Clay, with bed of large clay-stones at 162, and 



clay-stones at 205 (sand\- at the base) 380 ... 434 



f Sand, shells and pebbles, with water (hard 

 I clay with green grains ; pale greenish 



j sand; pebbles) 14 ... 448 



( Clay (brownish-grey) and black pebbles i:; ... 460 



^ Black peat (lignity clay) 2 ... 462 



Clean (sharp grey) sand 10 ... 472 



! Peat (lignite and lignity clay) 5 ... 477 



j (Coarse gre}') sand (or grit, with wee 



I pebbles of quartz) 2 ... 479 



'- Peat (hard lignite) 2 ... 481 



' (Brownish-grey, fine, sharp) sand 27 ... 508 



Clay (pale grey, and more or less sandy 



at 545- 547, 549, 55o, 555, 560) .....'. 54 ••• 562 



Sandy clay, with water 13 ... 575 



Clay II ... 5S6 



Green sand, with water (green-coated 



flints in sandy clay with green grains) i ... 587 



/■ Soft chalk ; clayey at 609 193 ... 780 



\ Soft chalk, with layers of flints at about 



4 feet intervals 70 ••• 850 



I Hard chalk, with flints (specially marked 



at869and875) 46 ...896 



[Blackheath 

 Beds, 26 

 feet ?] 



[Woolwich 

 Beds, 21 

 feet ?] 



[Thanet 

 Beds, 106 

 feet :-] 



[I'pper 

 Chalk, 309 

 feet.] 



