—Like woods each metal has its especial uses and it will depend largely on what you are going to make as to the kind of metal you should make it of.
There are five chief metals and a couple of alloys, which are formed by melting and mixing two or more metals together, which you will find the most useful and I shall describe these for you in detail.
Iron.
—This is the most useful metal we have. When it is pure it has a silvery color, is very tenacious, which means that it is tough; it is malleable, that is it can be hammered without cracking, and it is ductile in that it can be drawn out into wire without breaking.
It is hard to get pure iron for nearly all of it contains a small percent of carbon, silica, phosphorus, sulphur or other elements. These substances in iron give it different properties. For instance cast-iron has a large amount of carbon in it; this kind of iron is good to cast into molds but it cannot be hammered or drawn without danger of cracking or breaking.
Wrought iron has very little carbon or other substances in it and this makes it easy to work because it can be hammered or drawn. Steel contains more carbon than wrought iron but it has less carbon than cast iron; steel can be cast, forged, tempered and hardened by heating it red hot and then suddenly cooling it.
Tin.
—This is a white metal that looks very much like silver, and it is so malleable that it can be hammered out into very thin sheets and which you know so well as tin-foil.
It is not found in very many places but the ancients called Britain the Tin Islands because they got it chiefly from there. What we ordinarily call tin is really tin plate, that is thin sheet iron coated with tin, and it is used as a covering for other metals because it does not rust or oxidize in air.
Tin is largely used in making alloys such as soft solder, type-metal, pewter, etc. It has a very low melting point.