Iron* 
197 
of iron-stones, and the effects which individually they 
produce, must lead to great uncertainty of operation in the 
; smelting process, wherein the beautiful (economy of na- 
ture, and even real property, will be often unprofitably sa- 
crificed to precedento 
Besides the above causes of alteration, dependent upon 
mixtures of the earths, the existence of oxygen in various 
quantities in the ores ought never to be overlooked in pro- 
portioning the cokes to the iron-stone. This powerful 
j agent whose form and substance constantly eludes our 
i vision ; whose existence is only ascertained by the won- 
! derful changes produced by its various combinations with 
the iron ; and whose presence in the same iron-stone, in 
various quantities, may produce such variety of result as 
to characterise the ores, as containing good or had iron, 
surely forms the most interesting mixture which ores or 
iron-stones possess. It will be a momentous epoch in 
I the manufacture of iron when the existence of such a prin- 
ciple shall be fully admitted by the manufacturer, and its 
agency, from certain visible effects produced, adopted to 
explain its accompanying phenomena. Till that period 
he will not perceive the utility of ascertaining the quantity 
|| of oxygen, and devising (economical methods of taking it 
from the ore. An attention to this powerful principle can 
alone root out those prejudices so inimical to the real inter- 
ests of the manufacturer, and which seem to glance at Na- 
ture, as having improvidently combined her most useful 
metal with mixtures which could resist the ingenuity of 
man, or set his comprehensive intellect at defiance. In the 
progress of this great inquiry, is it not possible that the 
present expensive exertions may in part be superseded ? 
Is it not possible, that, by laying open the sources of infor- 
mation to individuals at large, a greater mass of intellect- 
may engage in the practice of this art ? While the present 
extensive and lofty buildings are necessary, the business is 
