68 Royal Institute of France. 



principles. Dr. R. having ascertained that the white opacity was 

 not the result of any chemical change, had recourse to optical 

 causes ; and he found hy forming one of the semi-transparent spe- 

 cimens into a prism, that the production of the opacity was owing 

 to this singular fact, that the refractive ])owcr of tabasheer is not 

 onlv lower than water, but so much lower as to be almost inter- 

 mediate between water and the gases. The physical properties 

 of tabasheer are not less singular than its optical qualities, and 

 indicate a structure of a very remarkable kind. 



May l;3.— A paper was read On the different QuaHties of the 

 Alburnum of Spring- and Winter-felled Oak Trees, by T. A. 

 Knight, Esq. 



Mav20. — Read An Account of certain Experiments made 

 with a' View of determining the Law of Attraction between Iron 

 and a Magnetic or Compass Needle, by P. Barlow, Esq. 



ROYAL INSTITUTE OF FRANCE. 



Public Sitting of the four Academies. 



In the public sitting of the four Academies of the Royal Insti- 

 tute of France, Mr. Charles Dupin delivered a discourse, the 

 subject of which was the influence of the sciences upon the hu- 

 manity of nations. In showing how far the sciences had not only 

 softened the manners of mankind, but also the otherwise inexo- 

 rable laws of war, Mr. Dupin quoted instances with respect to 

 England and France, which claim the admiration of all the friends 

 of civilization. 



The following are the examples alluded to : 



" For three centuries we have witnessed the Learned Societies 

 of all polished nations united in one fraternal bond ; not only the 

 learned of a single empire, but the most celebrated philosophers 

 of all nations. From everv quarter an appeal has been made to 

 every talent, and prizes offered for the research of great truths, or 

 their application to the useful purposes of mankind. 



" Crowns of merit have been awarded by the Amphictyons of 

 science to the superior talent of all, without the invidious distinc- 

 tion of native and foreigner. 



" Nor has war restrained the limits of this peaceful concourse. 

 The Society where Newton once presided, had founded a prize 

 for the greatest discovery relative to the laws of light and heat. 

 The theory of Malus respecting the polarization of light merited 

 tlie prize. The judges were English, the .author a Frenchman : 

 the war was at its height, and the two countries were exaspe- 

 rated by victory and defeat, by the songs of a Tyrtaens and the 

 harangues of orators, by fallacious pamphlets and the hirelings of 

 a policy without shame or remorse. 



" But 



