462 Philosophical Society of London. 



been bodily raised or depressed by some unknown force 

 applied to them, subsequently to the formation of the bed 

 of London clay. 



If a line in the direction of the central ridge of the Isle 

 of Wight, be extended westwards into Dorsetshire, it 

 will be found to coincide nearly with the direction of a 

 ridge running from Handfast Point to Lulworth, and with 

 that already described; and which therefore may be consi- 

 dered as a continuation of this former. 



The nearest tract of chalk to the north of this ridge is 

 the South Downs, the strata of which, together with their 

 superimposed beds up to the London clay, dip gently to 

 the south. Hence the space between may be considered as 

 a great basin or hollow, occasioned probably by the rup- 

 ture and subsidence of strata originally horizontal. 



Within this basin at its southern edge, that is on the 

 northern coast of the Isle of VVioht, occurs a large mass of 

 horizontal strata in many parts visibly resting on the edges 

 of the elevated strata above mentioned, and therefore he- 

 longinc to a period subsequent to that in which the forma- 

 tion ot the basin took place. This horizontal deposit differs 

 in its geological situation, in its mineralogical characters, 

 and in the fossils which it contains, from any others 

 that have hitherto been discovered in England ; but re- 

 markably corresponds in many of its members with the 

 beds found in the basin of Paris, and recently described by 

 MM. Cuvier and Brongniart; authenticated specimens of 

 which, sent by the latter of these gentlemen to the Count de 

 Bournon, have been by him deposited in the cabinet of the 

 Geological Society, 



These beds as they appear in the Isle of Wight consti- 

 tute four formations : the first of which is the lowest fresh- 

 water formation ; the second is the upper marine formation ; 

 the third is the upper fresh-water formation ; and the 

 fourth or superficial is an alluvial bed. 



The particulars of these are described in the subsequent 

 part of Mr. Webster's paper, which has not yet been read 

 before the Society. 



PHILOSOPHICAL SOCIETY OF LONDON, 



[Continued from p. 308.] 



The following curious relation was mentioned bv Dr. 

 Lettsom, as occurring to an old and esteemed school-fellow. 

 His propensity to spirits had become so irresistible, that 

 when he had been debarred from the more grateful flavour 

 of gin, rum, and brandy, he had purchased privately the 



nauseous 



