536 BRONZE 



yery satisfactory manner, that the metallurgists of Assyria wore perfectly conversant 

 with the use of iron, and that they employed it for the purpose of imparting strength 

 to the less tenacious metals which they employed in their art-manufactures. This 

 bronze, as analysed in the Metallurgical Laboratory of the Museum of Practical 

 Geology, consists of copper 88-37, tin 11 '33. 



Examination has shown that all the bronze weapons of the Greeks and Eomans were 

 not only of the true composition for insuring the greatest density in the alloy itself, 

 but that these, by a process of hammering the cutting edges, were brought up to the 

 greatest degree of hardness and tenacity. 



Before 1542, 'brass ordnance' (bronze) was founded by foreigners. Stow says 

 that John Owen began to found brass ordnance, and that ho was the first Englishman 

 who ever made that kind of artillery in England. 



Bell founding followed. Bell-metal and other broken metal were allowed to be 

 exported hitherto ; but it being discovered that it was applied to found guns abroad, 

 ' brass, copper, latten, bell metal, pan metal, gun metal, and shroff metal, are pro- 

 hibited to be exported." 



Bronze has almost always been used for casting statues, bassi-rilievi, and works 

 which are to bo exposed to atmospheric influences. In forming such statues, the 

 alloy should be capable of flowing readily into all the parts of the mould, however, 

 minute ; it should be hard, in order to resist accidental blows, be proof against the 

 influence of the weather, and be of such a nature as to acquire that greenish oxidised 

 coat upon the surface, which is so much admired in the antique bronzes, called patina 

 antiqua. The chemical composition of the bronze alloy is a matter therefore of the 

 first moment. The Brothers Keller, celebrated founders in the time of Louis XIV., 

 whose chefs-d'oeuvre are well known, directed their attention towards this point, to 

 which too little importance is attached at the present day. The statue of Desaix, in 

 the Place Dauphine, and the column in the Place Vendome are noted specimens of 

 most defective workmanship from mismanagement of the alloys of which they are 

 composed. On analysing separately specimens taken from the bas-reliefs of the 

 pedestal of this column, from the shaft, and from the capital, it was found that the 

 first contained only 6 per cent, of tin, and 94 of copper, the second much less, and 

 the third only 0'21. It was therefore obvious that the founder, unskilful in the melting 

 of bronze, had gone on progressively refining his alloy, by the oxidisumcut of the tin, 

 till he had exhausted the copper, and that he had then worked up the refuse scoriae in 

 the upper part of the column. The cannon which the Government furnished him for 

 casting the monument consisted of : 



Copper 89-360 



Tin 10-040 



Lead 0-102 



Silver, zinc, iron, and loss 0-498 



100-000 



The moulding of the several bas-reliefs was so ill executed, that the chiselors 

 employed to repair the faults removed no less than 70 tons of bronze, which was 

 given them, besides 300,000 francs for their work. The statues made by the Kellers 

 at Versailles were found, on chemical analysis, to consist of: 



No. 1. No. 2. No. 8. The mean. 



Copper . . 91-30 . . 91'68 . . 91'22 . . 91-40 



Tin . . . 1-00 . . 2-32 . . 1'78 . . 1'70 



Zinc . . 6-09 . . 4'93 . . 6.57 . . 6-53 



Lead . . 1-61 . . 1'07 . . 1'43 . . 1-37 



100-000 100-000 100-000 100-000 



The analysis of the bronze of the statue of Louis XV. was as follows : 



Copper . . . 82-45 Its specific gravity was 8-482 



Zinc .... 10-30 

 Tin .... 4-10 

 Lead .... 3-15 



100-00 



The bronzes of Franco, according to M. L. E. Riyot, contain nearly always four 

 metals, copper, tin, lead, and zinc. They may contain also very small and variable 

 quantities of iron, nickel, arsenic, antimony, and sulphur. 



