42 



Toom to crystallize. This will be readily understood by the 

 figure of what I have called Arborescent Copper. 



Copper is so well known in Great Britain as scarcely to 

 need a description. The fresh fracture is very hackly, 

 mostly brighter, and lighter in colour, than the outside, 

 which is often stained or cankered. It is however sometimes 

 found so pure, or bright, that it changes but little ; and the 

 fracture will hardly show a difference of colour, if carefully 

 kept. Hardness 6 — 8, Kirw. Steel cuts it neatly, whence 

 it is made into plates for engraving on. It is soluble in 

 acids ; and aquafortis is used by artists to etch upon it with 

 the help of wax, not unlike the operation spoken of under 

 the article Fluor, tab. xi. of this work. It is manufactured 

 for many purposes, as common coin and kitchen utensils, 

 but is not now so much used for culinary purposes as formerly. 

 It forms a compound metal with tin and zinc, called brass. 

 It is readily drawn into wire, which is very tough and durable. 

 A wire one-tenth of an inch in diameter will sustain 299y 

 pounds weight. 



