394 Scientific Intelligence — Geology. 



will therefore be indispensable for the maintenance of organic life on 

 its surface. The beautiful experiments of Saussure on the influence 

 of the carbonic acid of the air on the nourishment of vegetables, are 

 no longer sufficient to explain the permanence of the composition of 

 atmospheric air. We see that phenomena entirely of a difi^erent 

 kind must be introduced for the solution of the question, and that 

 the mineral elements of the crust of the earth likewise concur, by 

 the inverse reactions the one on the other, to produce this equi- 

 librium." — From, L'lnstkut, No. Supplement, p. 22. 



11. Geological Societi/, March 8. — Sir H. T, de la Bcche in the 

 Chair. — A paper " On the Position in the Cretaceous Series of 

 Beds containing Phosphate of Lime,'"' by R. A. C. Austen, Esq., 

 was read. — In a letter in the Gardeners' Chronicle of the 19th of 

 February last, Mr Paine of Farnham gives an account of some 

 strata in which phosphate of lime occurs in sufficient ahundance to 

 render it of importance to agriculture ; and the editor expresses a 

 hope that the notice may lead to the successful search for like under- 

 ground wealth in other parts of the country. The present paper is 

 written in part- fulfilment of that hope. Many observers, as M. 

 Brongniart, Dr Buckland, Sir H. do la Bechc, and Dr Fitton, have 

 noticed the occurronco of phosphates of limo in the gault. The 

 author had also noticed them in his account of the vicinity of Guild- 

 ford. The important part of the recent discovery is, therefore, only 

 that this substance is so abundant as to have great economic value. 

 Near Guildford, phosphate nodules are abundant in the upper green- 

 sand. In the gault below, concretions of phosphate of lime are not 

 so uniformly diffused, but occur in two seams — one in the argilla- 

 ceous portion of the bed, the other very low in the mass. Both beds 

 are very persistent ; but in consequence of the undulations of the 

 strata along the base of the escarpment of the Noi'th Downs, it is 

 only a few places that will repay those who may look for this mine- 

 ral substance, the beds of ganlt and greensand being often far be- 

 low the surface. The phosphates have been found beneath New- 

 land's Corner, near Guildford, at Puttenham, and other places. The 

 greensand and gault at Farnham also contain beds productive of 

 phosphates of lime. The nodules have the form of coprolites, but 

 differ from these bodies in internal structure. — Athenceum, No. 

 1064, p. 296. 



12. On the Presence of Phosphoric Acid in the Subordinate Mem- 

 bers of the Chalk Formation, bi/ J. C. Nisbet, was next read. — From 

 the marl near Farnham there was obtained by washing a substance 

 evidently coprolitic, containing 28 percent, of phosphoric acid, while 

 the general mass contains as much as 2 to 3 per cent. In some 

 nodules from the gault near Maidstone so much as 23 per cent, was 

 also ubtained, and some nodular masses of shells from the Shanklin 

 Sands, shewed 15 per cent, of this important substance. — Atlienceum, 

 No. 1064, p. 296. 



