from the Museum of the Royal Irish Academy. 333 



so too, and Aristotle and Pliny speak of it as a known and common substance. 

 Yet antiquities of tliis metal unalloyed are very rare ; indeed there have been, 

 I believe, but three instances recorded in which such have been found in Great 

 Britain, — and these all in England.* Hence a single additional specimen found 

 in the collection of the Academy acquires considerable interest. It filled the 

 interior of a hollow bronze ring of about four inches and a half in external 

 diameter, the thickness of the ring being about half an inch. It was easily 

 recognised as tin by its colour and the resistance it offered to the knife, and on 

 chemical examination it proved to be nearly pure, containing mere traces of 

 iron and lead. Where partially exposed to the atmosphere it had acquired a 

 coating of peroxide. From the way in which it is attached to the bronze, and 

 the character of the latter, it would seem with little doubt to belong to the 

 same period as the other early bronze antiquities in the Museum. 



In the collection there is an earthen vessel, apparently intended to be placed 

 in the fire, in which were found several small fragments of bronze very much 

 corroded, a brown earthy powder in which particles of the " ajrugo" of bronze 

 were observable, and a bit of a white metal of considerable lustre, and exhibit- 

 ing a somewhat lamellar structure. This latter was hard and very brittle, so 

 as to be easily reduced to powder in a mortar. There were no traces of corro- 

 sion on the surface. Specific gravity, 8'107. On analysis it gave in 100 parts, 



Copper, 6612 



Tin, 30-G2 



Silver, -13 



Antimony, 1-91 



Sulphur, 'll 



98-89 



Thus, though an alloy of copper and tin, it differs totally from bronze in the 

 proportion of its ingredients. The only analysis I have seen which comes near 

 this is that of an antique Roman mirror by KLAPROTH.f in which he found, cop- 

 per, 62 ; tin, 32 ; and lead, 6 ; = 100. Whether the Irish alloy was intentionally 



* Phil. Trans, vol. xxiii. p. 1129, and vol. li. p. 13. Arcbseologia, vol. xvi. p. 137- 

 f Scherer's AUgem. Journ. d. Cliemie, No. 33. 



2x2 



