%$$ French National lnjlitute. 



learned men, aiTembled at Paris, for fixing the new mcafures. 

 If it be difficult to attain to greater precifion, it will at lead 

 be interefting to fee how far the refults obtained are confirmed 

 by a method absolutely different. 



C. Flaugerges read feveral memoirs, containing obfer- 

 vations on various fubjecls ; as, on the phofphorefcence of 

 earth worms ; on the effects of thunder ; on halos, or lumi- 

 nous rings around the fun ; experiments tending to prove 

 that the fhadows of opake bodies, expofed in the open fields 

 to the light of the fun, when the fky is ferene, and projected 

 on a white furface, are always blue, or, more correctly, of 

 the colour of the heavens : and, in the laft place, experiments 

 from which it refults, that the waves, produced at the furface 

 of the water by percuffion, do not produce a movement of 

 tranflation in the parts of the fluid, as has been believed, ac- 

 cording to Newton, but only a continued depreffion of intu- 

 mefcence, which is afterwards propagated circularly. 



C. Brilfon haspublifhed Phyfical Principles of Chemifiry, 

 deflined as a fupplement to his Principles of Natural Philo- 

 iophy. The author compofed this work chiefly for the ufe 

 of the (Indents in the central fchools. It contains, in a clear 

 and methodical order, an account of all the fubflances 

 which fall within the province of chemiltry, an analyfis of 

 them, their fpecific gravities and other moil remakable pro- 

 perties, with a defciiption of the principal kinds of apparatu* 

 employed for chemical experiments*. 



C. Lacroix has publifhtd his Treatife of Differences and 

 Series, forming a continuation of his Treatife on the Differ- 

 ential and Integral Calculus. This important work com- 

 prehends in one fyftein the methods fcattered throughout dif- 

 ferent academical collections, and in the works of the greatell 

 geometricians of modern times. The fame author has 

 publifhed a fecond edition of his Treatife of Trigonometry, 

 and the application of Algebra to Geometry. 



C. Arboguft has juft publifhed a large work, entitled The 

 Calculus of Derivations. The author gives the name of de- 

 rivations to quantities deduced from each other by an uniform 



* We are happy *° learn that a tranflation iif this very ultful woik is 

 »a\* iu die prtfs, and will loon be publifhed. 



proceft 



