190 ON DEEP BORINGS. 



From a few of the cores which were examined by Mr. C. Moore, of 

 Bath, that gentleman obtained no fewer than 160 species of fossils, 

 chiefly of almost microscopic size. 



The boring at Ware (twenty miles north of London, in Herts) revealed 

 the presence of Upper Silurian rocks at a depth of 800ft. ; they were 

 Wenlock shales, resembling in every respect the well-known beds at 

 Dudley, and crowded with characteristic fossils, which have been 

 determined by Professor Etheridge. Lastly, at Turnford,|near Cheshunt, 

 some six miles south of Ware, Upper Devonian rocks were entered at a 

 depth of 935ft. 



These borings tell us that the theory promulgated long ago by Mr. 

 G-odwin Austen, that a ridge or axis of Palaeozoic rocks extends from the 

 coal basin of Somersetshire eastwards under London and Calais to the 

 Ardennes is a correct one. These old rocks have a high dip, and 

 probably undulate considerably. In some of their folds coal basins may 

 lie, and, as we now know that the beds strike east and west with a 

 southerly dip, it would seem probable that the upper carboniferous rocks 

 (coal-measures) lie somewhere under the south of London, and, if 

 another attempt should be made to reach them, this would be the most 

 likely spot. 



Further south the Oolitic rocks attain a great thickness, the Kim- 

 meridge clay being shown by the Sub-Wealden boring (at Netherfield, 

 near Brighton) to be 1,450ft. thick; but the section of this bore- 

 hole is not contained in our plate, and must be reserved for another 



note. 



SPONGES.* 



BY H. J. CARTER, F.R.S., &C. 



From the age of Alexander the Great, viz., in the fourth century 

 B.C., when, according to Aristotle, sponge (airdyyos) was "placed beneath 

 helmets and thigh-pieces for the sake of deadening the sound of blows," 

 (? the effect of blows,) almost down to the present time, the Officinal 

 Sponge has been considered chiefly in respect to its uses ; and even now 

 a sponge to many is but a sponge in this sense, " and nothing more." 



In these days of objective enquiry, however, the human mind, for 

 the most part, is not so stolid ; but, seeking eagerly, like a mariner for the 

 relation of surrounding objects that he might be the better able to find 

 his own position on the chart, becomes curious, among other things, not 

 only to consider the various uses to which the Officinal Sponge may be 

 applied, but to know what it is, whence it comes, and what position it 

 holds in the great mass of living beings that is spread over the surface of 

 our earth. 



*Conamnnicated by Mr. W. R. Hushes, P.L.S., to the general meeting of the 

 Birmingham Natural History ami Microscopical Society, held Tuesday, 29th June, 

 18S0. On Mr. Carter's behalf, Mr. Hughes also exhibited typical specimens illus- 

 trating the eight orders of Spongida mentioned in Mr. Carter's paper. 



