THE HAMILTON ASSOCIATION. 29 
of these men to any industry. Thirty years ago the manufae- 
ture of iron was wholly in the hands‘of these men. They made 
iron from the ores and converted it into steel, or rather wrought 
iron, by methods handed down from their fathers and improved 
upon by their own experience. They worked ‘‘by rule of 
thumb,’’ and in the making of pig iron they had about reached 
their hmit. With the introduction of chemistry, iron-making be- 
came an accurate, saientifie process. The defects and limita- 
tions of old methods were pointed out and direction was given 
to the lines along which the industry could be improved. As I 
have said, this is the peculiar virtue of chemistry, that it comes 
to the industry when it has been developed to its highest point 
mechanically, decides if any further improvement can be made, 
indicates along what lines such improvement is possible, and 
tells us exactly how far such improvement will extend. 
To illustrate, Sir Lowthian Bell was the first to study scien- 
tifically the chemical reactions which take place in the blast 
furnace, and the result of his investigation was to show that the 
carbon in the fuel is burnt to carbon monoxide inthe hearth 
of the furnace. That this carbon monoxide then acts on the 
ore in the upper part of the furnace, taking hold of the oxygen 
of the ore and setting the iron free. Now, it was shown that 
though this is the way in which a good deal of the ore is reduced, 
it was also shown that considerable of the ore found its way in- 
to the hearth, where it was reduced by the white hot carbon of 
the fuel. Now, here entered the special function of chemistry. 
By ealeulating the heat units absorbed and evolved in these re- 
actions it was proved that the more ore which reached the 
hearth unreduced by the gas and which had to be reduced 
by the solid carbon the more fuel would be required 
for the operation. It was apparent from this that if the 
ore could be kept from direct contact with the fuel and al- 
lowed to be acted upon only by the gas a great economy in fuel 
would result. The only way to accomplish this perfectly was 
to build two shafts or furnaces, charging the one with coke only 
and the other with ore only, burning the coke in one and driv- 
ing the resulting gas through the other. This has never been 
