120 Professor Brande on the Manufacture 



annealing, must be carefully protected, so that the work may 

 not be injured. 



Thus, after repeated blows in the die-press, and frequent 

 annealing, the impression from the matrix is at length per- 

 fected, or completely up, and having been touched up by the 

 engraver, is turned, hardened, and collared, as the matrix, 

 of which it is now a complete impression in relief, and, as we 

 have before said, is called a punch. 



This punch becomes an inexhaustible source of dies, without 

 further reference to the original matrix ; for now by impressing 

 upon it plugs of soft steel, and by pursuing with them an 

 exactly similar operation to that by which the punch itself was 

 obtained, we procure impressions from it to any amount, which 

 of course are facsimiles of the matrix, and these dies being 

 turned, hardened, pohshed, and, if necessary, tempered, are 

 employed for the purposes of coinage. 



The distinction between striking medals, and common coin, is 

 very essential, and the work upon the dies accordingly adjusted 

 to each. Medals are usually in veiy high relief, and the effect 

 is produced by a succession of blows ; and as the metal in 

 which they are struck, be it gold, silver, or copper, acquires 

 considerable hardness at each stroke of the press, they are re- 

 peatedly annealed during the progress of bringing them up. 

 In a beautiful medal, which, as well as the dies for it, I have 

 had lent me by Mr. Wyon, and which he has just completed 

 for the Royal Naval College, the obverse represents a head of 

 the King, in very bold relief; it required thirty blows of a very 

 powerful press to complete the impression, and it was necessary 

 to anneal each medal after every third blow, so that they went 

 ten times into the lire for that purpose. In striking a coin or 

 medal, the lateral spread of the metal, which otherwise would 

 ooze out as it were from between the dies, is prevented by the 

 application of a steel collar, accurately turned to the dimensions 

 of the dies, and which, when left plain, gives to the edge of the 

 piece a finished and pohshed appearance; it is sometimes 

 grooved, or milled, or otherwise ornamented, and occasionally 

 lettered, in which case it is made in three separate and moveable 

 pieces, confined by a ring, into which they are most accurately 

 fitted, and so adjusted that the metal may be forced into the 



