Mr, J. Taylor's Leduiei on Metallurgy, 287 



prized articles : while in the history of the civilized world, we 

 may observe that metallurgic processes were greatly esteemed 

 and eagerly pursued, and proficients in the art by which the 

 metals were worked were honoured for their knowledge and 

 enriched by their skill. 



The metals will appear upon the slightest consideration of 

 the subject to form a principal ingredient in most operations 

 conducive to our comfort, amusement, or improvement. With- 

 out them, we can conceive of no fit instruments of agriculture, 

 art, or scientific research. 



Their uses may be said to be both active and passive ; for 

 while they furnish us almost entiiely with the tools by which 

 substances of every kind are moulded to their destined form, 

 they are likewise in themselves a principal material to be 

 worked upon. The copper plate which receives the most deli- 

 cate forms that the engraver can pourtray, takes its impres- 

 sion fi'om the hard and pointed steel. The various properties, 

 then, which peculiarly render the metals applicable to so many 

 purposes, are (as has been stated above). Peculiar Lustre — 

 Opacity — Specific Gravity — Fusibility — Extensibility (includ- 

 ing Malleability and Ductility) — Tenacity: 



Also those properties which they possess in common with 

 other substances: — such as Divisibility and PenetrabiUty, 

 Elasticity, Affinity for each other, and Affinity for other sub- 

 stances. 



1st. From the first of these properties, — the metallic lustre 

 and the susceptibility of polish, — results not only all the bril- 

 liancy which delights the eye under so many varying forms 

 and circumstances, but also the perfection of mirrors and the 

 specula which have so much improved our telescopes. 



2dly. The specific gravity of the metals is attendant upon 

 that solidity and strength which forms a very prominent quality 

 in fitting them for many important uses. The density which thus 

 belongs to them enables us to employ them for vessels which are 

 to retain or conduct the most subtile vapours, such as steam 

 and the gases ; and, as it is combined with ductility, to con- 

 fine and employ them in the full energy of highly expansive 

 force. 



3dly. The third property of the \neiii\s, fusibility, gives rise 

 to the art oi founding, by which forms are pi'oduced in endless 

 succession, similar to any given pattern and similar to each 

 other, and without the labour of working them into shape by 

 long continued exertion. It is only necessary to mention the 

 great use that is now made of cast iron and brass, as instances 

 of the a))plication of this property. 



As a part of the fusilMlity of metals, xvel(fi?ig may be noticed, 



wliich 



