308 THE WORLD'S LUMBER ROOM. 



them, the dustmen do not like them, and when the fashion 

 was declining some years ago it is said that numbers were 

 thrown into the streets of New York and other towns, 

 where they were not only a nuisance, but dangerous, both 

 to foot-passengers and horses. Yet enormous quantities of 

 steel must be used in their manufacture, and this, of 

 course, could be melted down. 



The monument to Horace Greeley, the founder of the 

 New York Tribune, is cast out of many thousands of 

 pounds of old type, contributed by the printers of the 

 United States. 



The scrap iron, or rather steel, left over from needle 

 making, being of the finest quality, is used for making 

 gun-barrels ; the waste from the steel pens made in Bir- 

 mingham is sold to Sheffield, at 10 a ton (the original 

 price having been ^50 or ^60), and is there re-melted. 

 Steel filings are bought by chemists for the manufacture 

 of steel- wine. 



Old ship's copper and copper-scraps of all kinds are 

 first converted into oxide by heat, and then dissolved in 

 sulphuric acid, forming sulphate of copper, which crystallises 

 in large blue crystals, and is commonly known as blue 

 vitriol, which is largely used in calico-printing and the 

 manufacture of various pigments, such as Scheele's green. 



Copper pyrites, or sulphide of copper, is used for the 

 same purpose, and as small quantities of gold and silver 

 are frequently associated with this ore, the residue from 

 the pyrites kilns in vitriol factories is found to yield both 

 these metals as well as copper. Gold and silver to the 

 value of ,3,232 have been obtained from 16,300 tons. 



