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to recommence work where it had left off. But, how is the core 

 snapped from its bed, and brought up in the anger ? This is done 

 by a very simple contrivance. A steel wedge, of about nine inches 

 in length, and an inch and a half wide at the top, — tapering from a 

 knife-edgo at the point, tu about half-au-iuch thick at the base, — is 

 fixed inside the auger. As the core rises in the augei", inside of 

 which it has from one to two inches play, it is pressed on one side 

 by the wedge ; and, being thus thrown out of the upright, readily 

 snaps asunder, when, resting upon the flanged inside edge of the 

 crown, it is easily brought to the surface. The auger is 25 feet 

 long, and brings up about 23 feet of core each time ; not all in one 

 piece, but of various lengths, according to the position in which the 

 wedge is placed. There is one long piece in the Brighton Museum, 

 but Mr. Willett showed his visitors a perfect column 7ft. Gin. in 

 length. As a matter of course, the depth obtained each day varies 

 with the substance pierced. The limestone has been the hardest, 

 and the Kimmeridgc clay the softest yet found ; and the penetra- 

 tion has varied from a quarter of an inch to two inches and a half 

 per minute. Numerous difficulties have had to be contended against, 

 not the least of which has been the fracture of cores caused by 

 fissures in the strata, when small wedge-like pieces would fall 

 between the core and the inner side of the auger, which, being 

 gradually choked up, has ceased to rotate round the coi-e itself, 

 thus giving the boring rods a violent and sudden twist. Another 

 difficulty met with has been the crumbling of the earth round the 

 outside of the auger, which has necessitated lining the bore with 

 tubes, not a very unimportant item in the expenditure. Lining 

 tubes, — the lengths being screwed and fitted to each other, — bad 

 been put down to a depth of 1,130 feet ! the weight of metal alone 

 being eight tons ! and the most successful piece of lining performed 

 was in piitting down 900 feet in 24 hours without an accident. 



Some very interesting specimens of the strata gone through — 

 including one composed entirely of oyster-shells, obtained at a 

 depth of 1,130 feet, — were shown ; and many pieces were brought 

 away as mementoes of the visit. 



Only a few yards from the Sub-Wealden Borings, a shaft has 

 been sunk by a Company for working, as a commercial speculation, 

 the gypsum beds which the Exploration Committee discovered ; and 

 a short visit was paid to these works. The sinking of the shaft has 



