15 



was unfavourable for such observations ; the higliest result was 840 lb. 

 on a square foot. The communication concludes with an ac- 

 count of several instances of the effects of the waves in the eleva- 

 tion of spray, and in the transportation of heavy masses of rock. 

 The greatest observed elevation of spray was at the Bell Rock 

 Lighthouse, on the 20th November 1827, during a calm with a 

 ground swell. On this occasion the spray was projected to the 

 lieight of 106 feet, which shews the existence, on the large scale, of 

 a pressure of about 3 tons. The pressure which projected this 

 column of spray exceeds, therefore, the greatest result obtained by 

 the Marine Dynamometer. The largest stone that is mentioned in 

 the paper, as having been moved by the sea, is 42 tons weight. 

 This stone, which is on the shores of one of the Hebrides, was seen 

 to move under the influence of each wave. 



4. A Verbal Communication in regard to Chevalier's Expe- 

 riments on the Decomposition of certain Salts of Lead 

 by Charcoal. By Dr Traill. 



The following Donations were announced : — 



Journal of the Royal Asiatic Society of Bengal. Nos. 144, 145. — 

 By the Socicti/. 



On the Nature of the Nervous Agency. By James Stark, M.D., 

 F.R.S.E. — B>/ the Author. 



Researches on the Brain, Spinal Cord, and Ganglia, with Remarks 

 on the Mode by which a continued flow of Nervous Agency is 

 excited in, and transmitted from, these organs. By James 

 Stark, M.l)., F.R.S.E.— ^3/ the Author. 



Philosophical Transactions of the Royal Society of London foi 

 1844. Part ii. 



Proceedings of the Royal Society of London. No. 59. — By the 

 Royal Society. 



Magnetical and Meteorological Observations made at the Royal 

 Observatory, Greenwich, in the year 1842, under the direc- 

 tion of George Biddell Airy, Esq., M.A., Astronomer- Royal. 

 — By the Royal Society. 



Outlines of Chemistry for the use of Students. By William Gre- 

 gory, M.D., Professor of Chemistry in the University of 

 Edinburgh. — By the Author. 



