35° Hiflorical Remarks relative to 
~ machinery had attained a pitch of certainty, and experience 
had taught the mechanic the manifold advantages to be 
derived from,the fteam-engine, men of induftry and enter-. 
prife began to think of extending the manufactures of the 
country in iron with pit-coal. Small furnaces fupplied with 
air from Jeathern bellows, blown by oxen, horfe, or human 
labour, became exploded, and an increafe of fize took place, 
-together with an increafe of the column of blaft neceflary to 
excite combuftion. But as it feldom happened, that to the 
advantage of having pit-coal, ores, and limeftone concen- 
trated in one fpot, water alfo was added, it became neceffary 
to form a fubftitute. For this purpofe, the fleam-engine, 
that fuperhuman invention, was applied. Rude and unpo- 
lithed no doubt were its early defigns and execution—rapid 
however have been its improvements; and .at the prefent 
time, by many it is believed to have arrived at the highett 
poffible pitch of human perfeétion. 
With the improyements in machinery the advancement 
in the practice of. manufacturing coak pig iron kept pace ; 
and it is now a certain truth, that with, pit-coal in our time 
we produce a quality of pig iron fuperior for every purpofe of 
the arts (bar iron making excepted) to, that at any time 
made with charcoal of wood, and in the following inereafed 
proportion ; 
Average annual produce of a charcoal furnace ° Tons. © 
180 years ago - - - - 600 
Some furnaces in England on an average; now 
produce 40 tons per week - - 2080 
Value of the former when manufa&ured £.6 per 
ton - - - - - £.36c0 
Value of the latter on an average of the qualities 
‘6/, tos. - - - - - £13520 
By comparing the value of pig and bar iron at prefent 
with what it fold for 180-years ago, an aceurate notion may 
be formed of the increafed price of labour and materials at- 
tached to iron works. 
‘About 
