68 Proceedings of Philosophical Societies. [Jan. 



in breadth, and from three to six feet in height along the middle. 

 About one-third of its surface was covered with stalactites of 

 arraoonite {flos ferri) of great beauty. This cavern is situated 

 in the greywacke ; and Mr. Anstice remarks, that the arbo- 

 rescences of arragonite occur only in that rock, while those 

 which are found adhering to the lime-stone are common calca- 

 reous stalactite. 



A letter was read from Mr. Winch, mentioning the discovery 

 of a tree about 28 or 30 feet long, with its branches, in a bed of 

 fire-stone (one of the coal sand-stones) at High Heworth, near 

 'Newcastle. Of this organic remain the trunk and larger branches 

 are siliceous ; while the bark, the small branches, and leaves, 

 are converted into coal : and Mr. Winch remarks, that the small 

 veins of coal, called by the miners coal-pipes, owe their origin 

 universally to small branches of trees. Mr. W. states it as a 

 remarkable and interesting fact, that, while the trunks of trees 

 found in the Whitby alum shale are mineralized by calcareous 

 spar, clay-iron-stone, and iron pyrites, and their bark is converted 

 into jet ; those buried in the Newcastle sand-stones are always 

 mineralized by silex, and their bark changed into common coal. 



A paper by Dr. Berger was read, containing a theoretical ex- 

 planation of the curvature of the beds of lime-stone which form 

 the Jura mountains. 



J) ec , 5. — The reading of a paper by Mr. W. Phillips, entitled, 

 " Remarks on the Chalk Hills in the Neighbourhood of Dover, 

 and on the green Sand and blue Marl overlying it near Folke- 

 stone," was begun. 



Dec. 19. — The reading of Mr. Phillips's paper was continued. 



ROYAL ACADEMY OF SCIENCES AT PARIS. 



Sept. 1, 1817. — The following papers were read : 



A memoir on aneurism, by M. Provencal. 



A description of the oyster-beds of Maremmes, by M. de 

 Montegre. 



An offer made by an anonymous individual to contribute a 

 sum of 7000 fr. for the purpose of founding a prize for the en- 

 couragement of inquiries into subjects connected with statistics, 

 Was referred to a committee. 



Sept. 8. — A letter from the Minister of the Interior was read, 

 communicating the King's approval of the election of M. Piazzi 

 into the class of Foreign Associates. 



A paper, entitled " Researches on Chlore and on Hydro- 

 chloric Acid," by M. Rosier, was referred to the consideration 

 of a committee. 



M. Lamarck gave an account of a paper addressed to the 

 Academy by M. Dupetit Thouars, on the renewal of the oark of 

 trees. 



M. Fourrier, in the name of the committee to which the offer 

 of an anonymous person to establish a prize for statistics was 



