VOL. LXXXVI.] PHILOSOPHICAL TRANSACTIONS. 5g 



nuity and skill for answering the main purpose of it, that of piercing armour. It 

 was found, together with another dagger, in Barling's Eau, near Short Ferry, 

 in 1788. 



4. A sword in its scabbard, fig. 4. I could not by any force draw it out of the 

 scabbard. On breaking the scabbard, I found the sword destroyed by rust; but 

 the guard and hilt were still in a metallic state, and the pommel had been broken 

 off. I have already described this instrument in the account of the brass arms. 



§ 2. Chemical properties. — 1. The sword, fig. 8. (a) Being filed and polished, 

 it was of the colour of steel. The blade was bent considerably before it was broken; 

 and could not be broken without considerable force. Comparatively with soft steel, 

 or malleable iron, it possessed little malleability. Under the hammer, file, and 

 drill, it felt as hard as hardened steel. The snipt edges were hard, and strong 

 enough to saw asunder the celts described in this paper. Its fractured surfaces 

 showed a silvery kind of open grain, like steel which has been hardened by plunging 

 it, when white hot, in cold water. The pommel and guard were much more mal- 

 leable, and much less hard than the blade. 



(b) The blade, when red-hot, was malleable, but much less so than our common 

 steel. On cooling gradually it became less hard than before; but it was not so soft 

 as our common annealed, or distempered steel. By plunging the distempered piece 

 of the blade, when white hot, in cold water, it was restored to its original hardness. 

 By plunging the pommel and guard when white hot in cold water, they were ren- 

 dered much harder; and by again igniting them, and letting them part with their 

 fire gradually, they became as soft as they were originally, (c) The specific gra 

 vity of the middle part of the blade, after filing off the coating, was 7.476. 



(d) The dissolution of 300 grs. of the blade in sulphuric acid and water, yielded 

 nearly the same quantity of hydrogen gaz as an equal quantity of our steel affords. 

 During the dissolution the mixture became black, and a black froth appeared on its 

 surface ; and, after repose, there was a deposit of black matter. The solution, 

 made boiling hot, was poured on a paper filter; and being filtrated, the filter was 

 edulcorated, by repeatedly pouring on it pure water. The paper filter was stained 

 black by the solution, and there was a small deposit of black matter in the apex of 

 the cone of the filter. This black matter was carbon, in about the same proportion 

 as our steel affords by the same treatment. The filtrated solution, on evaporation, 

 was found to contain nothing but sulphate of iron. 



(e) A little nitric acid being dropped on the polished surface of the blade; and 

 also on the pommel and guard; a black spot was produced on the parts wetted, 

 (f) The tinned part of the pommel being just wetted with nitric acid, it became 

 white. 



2. The axe, fig. 9. (a) Being polished, it appeared of almost a silvery whiteness. 

 — It was harder than malleable iron, but was not so hard as hard steel, for it was 

 easily filed, and bored through with the drill. It was also cut through, and the 

 cut surface was smooth and uniform, and close, as if made of the purest metal. 

 It bent a little, notwithstanding its form and thickness; and required a very smart 



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