596 Miscellaneous. [Nov. 



lbs. of tin. For small bells and cymbals, the two metals must be purer than for 

 gongs. 



The gong must not be cast of the necessary form, and afterwards forged under 

 the hammer: but first a thick disc must be cast, then cut round and forged. If 

 large, the instrument must be laid on the ground, and four or five workmen em- 

 ployed to hammer it. By degrees it spreads and rises on the edges, when it be- 

 gins to give out sounds like those of a musical cord from the points struck by the 

 cold hammers. 



In the centre of the plate a boss or knob is left, on which the blow is to be 

 given :— two sorts of sound are recognised, the male and female, depending on the 

 form and projection of the boss. 



On doubling the blows of the hammer, the instrument gives out a grave tone.' 



To this unsatisfactory extract M. Darcet has appended a note, of which the fol- 

 lowing is the purport. 



The analysis of seven tam-ta.msa.nd. 22 Chinese cymbals confirmed the composition 

 stated of 80 copper -f 20 tin* : it contains no bismuth. This compound metal is well 

 known to be as brittle as glass, and far from submitting to the hammer after be- 

 ing cast it would hardly bear the blow of a striker. Moreover it is more brittle when 

 heated, andmay then be pulverised. This alloy is also dense, the fracture a finegrain 

 like bell-metal, whereas the gongs and cymbals are of less specific gravity, a fi- 

 brous structure, and a colour similar to that of an alloy of 90 C. ■+- 10 T, or gun 

 metal : they may be hammered out and bent with ease. 



It is evident, therefore, that there must be some secret in the fabrication of these 

 instruments, and this M. Darcet supposes to be the mode of tempering. In 

 fact he finds that the alloy in question raised to a cherry-red heat, and then plunged 

 into cold water, assumes all the properties of the tam-tam and cymbal metal :— 

 This skilful chemist has constructed more than 60 pair of cymbals thus, and 

 always found the simple expedient successful. The Chinese account is entirely 

 silent as to any such treatment of the alloy. 



After tempering, however, the alloy is still much too brittle to be worked under 

 the hammer: — the Chinese workmen must therefore have deceived the author of 

 the article ; and the translator is also at fault in supposing that it is more easily 

 forged hot. 



The method followed in China is thus conjectured by M. Darcet : An exact mo- 

 del of the instrument required in lead or pewter is first madef, over which a mould 

 of sand or clay is made. The alloy is fused, cast into an ingot, remelted and cast 

 into themouldj. 



The cast is then dressed (ebarb^e) and tempered like steel. The tone may be 

 regulated by the highor or lower temper given, or by gentle blows over the surface 

 to shape and finish it. France now rivals China in the excellence of her cymbals 

 and tam-tams, 



* This is also the composition of the Japanese mirrors. See Journal As. Soc. vol. i. 

 p. 243.— Ed. 



f This is a very common practice in India. — Ed. 



X Probably the Indian mode of attaching the mould to the top of the crucible is fol- 

 lowed, as by this means it is warmed and receives the metal freely. — Ed. 



