12. Geology, Mineralogy, Scenery, &c. 
Other Furnaces. 
We soon arrive at the Wanscopommuck or Furnace lake, 
a happy natural reservoir, of a mile or two in diameter, which 
supplies an unfailing stream for some of the most conside- 
rable iron furnaces in this interesting district of country. 
By the politeness of one of the proprietors* every facility 
was afforded of access to the iron establishment and to the 
bed of ore. 
The establishment is more considerable than the one al- 
ready described, and I was particularly struck with the im- 
mense piles of slag and refuse, accumulated around the fur- 
naces. 
It also struck me forcibly at both places, that the twyers 
(tubes) of the bellows instead of being fixed, air tight, into 
the side of the furnace by which means, at first view, one 
would suppose that the greatest quantity of air would be 
thrown in, and the smallest wasted, were brought only within 
a few inches of the furnace, and discharged their blast into 
an orifice of much greater surface than that of the tubes ; 
experience, it seems, has shewn, that this is the best arrange- 
ment, and that more heat is thus excited than upon the other 
plan. May notthe effect be accounted for, froma powerful de- 
termination of the atmosphere (created by the heat of the fur- 
nace) to enter at the same place, which as there is no grate 
and no admission of air from below, could not happen pro- 
vided the twyer were fixed air-tight into the furnaee. Ai this 
establishment they have cast cannon forthe navy. They 
are cast solid and then bored out by a rotary movement 
produced by water. By particular management im the re- 
duction of the iron ore, they produce at pleasure either a 
harder or a softer metal; the hardest is so hard that it cannot 
be filed, bored, or in any way altered; this is the fact with 
most common articles of domestic hollow ware, but that 
cast for cannon and some other purposes is soft and is much 
tess brittle than the hardest kind. 
Salesbury iron ore bed. 
‘The main iron ore bed is situated two miles West of 
these furnaces. This of course formed an object of atten- 
“John M, Holly Esq. 
