214 IRON 



from falling through the holes, but it is made white hot and 

 forced to bubble about like water boiling inside a kettle. The 

 air-blast is continued until all the carbon in the iron has united 

 with the oxygen of the air. (This takes about twenty minutes, 

 and during this time some of the other impurities unite with 

 the oxygen and form other oxides.) 



Next molten spiegeleisen is poured in. This is a mixture 

 containing iron, carbon, and manganese, in known proportions, 

 so that the amount of carbon added to a given amount of iron 

 can be regulated. 



The steel is then poured into moulds, and left until the 

 outside has become solid, and while still hot is pressed between 

 shaped rollers, and finally is cut into the lengths required. 



The iron most suitable for this process is the Red Haematite, 

 which occurs in great abundance in the Furness district of 

 North Lancashire. Barrow is the centre of this district. 



Iron is also mined : 



(a) In the oolitic limestone of (i) the Cleveland district of the 

 North York moors. The ore which occurs here is an impure 

 form of clay-band ironstone, yet it is from this region that we 

 obtain nearly half our total output of iron. Middlesbrough 

 is the chief town, (ii) The hills of Lincolnshire, Leicester, and 

 Northampton. 



(6) In the carboniferous limestone of South Lancashire, North 

 Staffordshire, South Staffordshire, West Cumberland, Ayrshire, 

 Lanarkshire, Stirling, Clackmannan, Edinburgh, and Fifeshire. 



The fact that so much of our iron was mined near our 

 coalfields, that these fields were near navigable rivers, or near 

 the sea- coast, and that it was in Britain that the chief inven- 

 tions connected with improved methods of producing iron 

 were made, caused us to become in the nineteenth century 

 the greatest iron-producing country in the world, but districts 

 that once produced iron produce them no longer, so that 

 we now stand third 1 among iron-producing countries and do 

 not produce much more than half the iron we require. It 

 1 1, the United States ; 2, Germany ; 3, Britain. 



