Imi* 
In Pennsylvania a cord, (8 feet by 4 feet and by 4 feet, 
or 128 cubic feet of wood, put up as close as the sticks 
! reasonably can be placed) of oak, will yield about 40 bush- 
els of coal ; a cord of pine, about 42 bushels : or it may 
be said that 100 bushels of wood coaled in the common 
way for the use of a furnace, will require two and a quar- 
ter cord of w T ood ; but if coaled for a bloomery or refinery, 
where the coal must be all of the best quality, 100 bush- 
els will require two and a half cord. The expence of 
cutting is about 40 cents a cord, coaling about 36 or 37 
cents* From 20 to 40 cords of wood are coaled at once 
upon one hearth. The quantity of coal used to produce 
a ton of metal will of course vary with the nature 
of the iron ore, and the skill of the founder or manager* 
Mushet reckons 16 cwt. of charcoal of wood to a ton of 
metal ; which I think is too little. In Pennsylvania I 
have heard it computed at 200 bushels, of about 141b. to 
the bushel, of dry charcoal. There is no ascertaining any 
fact of this kind by weight ; because, good well burnt 
| charcoal will imbibe from the atmosphere in the course 
of 3 or 4 days, 12 or 13 per cent, of air and moisture : but 
on this calculation, the English (or rather the Scotch) ma- 
il nagers make, a ton of iron with a fourth less coal than the 
I American. Good charcoal should ring with a metalline 
sound : it will frequently strike fire with steel. Charcoal 
exposed to moisture, and kept together in great heaps, 
has been known to take fire spontaneously. I suspect 
I charcoal is the worse for the moisture it imbibes ; for in 
the heat of a furnace, the water will be decomposed both 
by the charcoal, and by the iron ; and as water contains 
eighty-five and two thirds per cent, by weight of oxygen, 
and only fourteen and one third of hydrogen, it appears 
to me, that coal must be greatly wasted by moisture ; but 
the subject is very difficult and complicated. 
I have met with no calculations on which any reliance 
