yQ SCIENTIFIC NEWS. 



which La second of the eccentricities and inclinations. Mr. La* 

 &r a "g e extenc] • grange, struck with this conclusion, endeavoured to extend 

 it. ; and proved by a curious theorem, that the proposition 

 was true, considering even all the successive powers of the 

 eccentricities. But what would be the result, were the 

 and Poisson masses considered in terms of two dimensions ? This inquiry 

 fUf^th demanded great labour, and no less acumen : yet Mr. Pois- 



sou undertook it, and demonstrated, that, if any accelera- 

 tion exist, it can only depend on terms of four, six, or eight 

 dimensions, and of course must be altogether imperceptible. 

 As soon as Mr. Poisson had demonstrated his theorem, Mr, 

 Lagrange and Mr. Laplace perceived, that, it naturally flow- 

 ed from principles and methods they had formerly laid 

 down: in consequence they were both led to demonstrate 

 the proposition more generally, but each in a different way. 

 History of the The physical division of the class presented to the em- 

 sciences. peror a sketch of the history of the sciences from the year 



1789, which will soon be published. 

 Discoveries in a he principal discoveries in chemical science are those to 

 chemistry. which Mr. Davy led the way, and which have been pursued 



in France chiefly by Messrs. Gay-Lussae and Thenard. 

 Minerals ex- The experiments of Sir James Hail too have been repeat- 

 posed to great € & b y M r> Dree. Having exposed to fusion in close ves- 

 heat under ,,•••., ,■ n , • , 



pressure sels, under irresistible pressure, fragments or rocks with. 



trap or chert for their base, he found, that they assumed all 



. . m the appearance of stony lavas ; and that the crystals of feld- 



tals not fused, spar in them were not altered, which explains the singular 



fact of so many very fus.ible crystals contaiued in lavas, that 



have rendered it questionable whether these lavas had ever 



•been in a state of fusion. 



_ , The invention of the art of laminating zinc by heating it 



Lamination of ° J » 



ainc, is claimed for the late Macquer and Mr. Sage, who practised 



it long ago: and Messrs. Dony and Poncelel, of the de- 



andits extrac- ' ~ 



tien from the partment of the Ourthe, have converted calamine simply by 

 ore§ subliming it into metal sufficiently pure to be laminable. 



The ore affords them one third its weight of metal, which is 

 much cheaper than lead. 

 Acetic »eid Another successful application of chemistry to the arts is 



Jiom wood. that of procuring from wood an acetic acid as pure as radi- 

 cal vinegar, the manufacture pf which has been carried on 



some 



