1818.] lioyal Academy of Sciences. 383 



of the several candidates for the prizes offered in natural philo- 

 sophy, mathematics, and chemistry. 



Jan. 12. — Committees were nominated to draw up reports on 

 the subjects and conditions of the prizes for next year, and to 

 adjudge the medal of Lalande. 



M. Percy made a report on several works and collections 

 relative to medicine. 



Jan. 19. — M. Pons, Directeur-adjoint of the Observatory of 

 Marseilles, announced that he had discovered a new comet. 



Several memoirs and machines were referred to the consider- 

 ation of committees. 



M. Cauchy gave in a memoir on the integration of a particular 

 class of differential equations. 



A paper, by M. Lacoste, M.D. entitled " An Essay on the 

 Means of preventing the Violence of Storins and the Production 

 of Hail," was read, and referred to a committee. 



Jan. 26. — The Minister of the Interior requested the Academy 

 to nominate a candidate for the situation of second Proj'esseur 

 adjoint in the School of Pharmacy at Montpelher. 



M. Devaux gave in a memoir on the glands of vegetables. 



M. Vauquelin read a memoir on the influence of the metals in 

 the production of potassium by means of charcoal. 



. A letter from M. Dupin was read, containing an analysis of a 

 work which he lias recently composed, entitled " Premier Voyage 

 en Angleterre." The object of" this work is to describe the 

 manufactories and public works of England as far as the author 

 has had an opportunity of examining them. 



The docks of the port of London are first treated of. M. Dupin 

 particularly notices the superiority in the construction of these 

 docks over similar works in France, depending on the curvili- 

 near form of the masonry with which the sides of the docks are 

 lined, and on the employment of the same principle in the con^ 

 struction of the locks. He notices also the employment of the 

 steam-engine in hydraulic constructions for all work which 

 requires great and long exertions on one spot, as in pumping, &c. 



The habitual use of iron rail-roads, the ease with which they 

 are taken up and laid down, and the great facilities thus afforded 

 for conveying bulky commodities, such as coals, limestone, iron 

 ore, 8cc. are next described. 



The improved dredging machines, worked by steam, for clear- 

 ing accumulations of mud in docks and rivers, and for removing 

 banks of gravel, and of other loose materials which impede inland 

 navigation, are noticed by the author with much approbation. 

 He notices also the employment of the diving bell as a substi- 

 tute for caissons in building under water, and in recovering from 

 the bottom of the sea in harbours, and roadsteds, anchors, 

 cannon, and the contents of sunken vessels. M. Brunei's ma- 

 chines for cutting veneers, for planing and sawing wood, are 

 next noticed ; and the report concludes with a description of the 



