463 



derived from (3) will contain two arbitrary constants, which 

 appears to be more in accordance with the recent experiments 

 of MM. Wertheim, Strehlke, and Kirchhoff, than the original 

 result of M, Navier, which makes the equations of a homoge- 

 neous solid depend upon a single constant. If in function (3) 

 G, H, &c., be constants, the linear part of the function will 

 produce no terms in the equations of motion, which will be- 

 come identical with the equations given by M. Cauchy for a 

 system of attracting and repelling molecules, when we do not 

 suppose the natural condition to be one of free equilibrium."* 



Mr. Donovan read a notice of the analysis of certain gold- 

 coloured bronze antiquities found at Dowris, near Parsonstown, 

 in the King's County. 



" At a late meeting of the Academy a communication was 

 made by Thomas L. Cooke, Esq., of Parsonstown, relative to 

 certain ancient bronze articles found at Dowris in the King's 

 County. Some specimens having been, by that gentleman, 

 placed in my hands for analysis, 1 deem it proper to lay before 

 the Academy the results of my investigation. The articles 

 given to me were part of a celt and a portion of a horn. 



" The golden hue of these ancient bronzes suggested to 

 some persons the idea that they contained an admixture of 

 zinc, an ingredient not hitherto, I believe, found to enter into 

 their composition. Such bronzes in the British Museum as 

 have been analysed consist of copper and tin only ; and the 

 Greek and Roman bronze coins are known to have been com- 

 posed of the same metals. Bishop Watson, it is true, sup- 

 posed that zinc constituted a part of a celt examined by him, 

 his proof being that the metal, when melted, emitted a thick, 

 white smoke, accompanied bya blue flame, which are esteemed, 



* Exercices de Mathematiques, vol. iv. p. 131. 



