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542 FORTIA’S TRAVELS IN SWEDEN.
From Gripfholm to Ofer is a mile, There is not an inn in the place, and no other
accommodation than what the houfe of Mr. Vahrendorf the proprietor affords, or thofe
of fome of the officers belonging to the foundry. So that in cafe of Mr. Vahrendorf
being abfent it may not be amifs to be provided with a letter from him : it will be ftill
better to wait until he may himfelf be there.
This place is very interefting on account of its handfome foundry for cannon.
Cannon foundry. The ore which is made ufe for founding cannon comes from fix dif-
ferent mines: it fhould be poor or at leaft mixed fo that the aggregate may contain no
more than thirty per hundred of metal, and particularly it fhould contain none of that
quality which breaks when hot. The firft roafting of the ore is carried on in the fame
manner asat Fahlun inthe open air. ‘There are two furnaces for the fufion, each acted
upon by two bellows; they yield a fchippund of iron per hour for cannon : every twen-
ty-four hours one piece of twenty-four pounds and one four-pounder are ca{t, or one
thirty-fix-pounder. ‘Thefe two furnaces require three hundred and twelve tons of
wood daily, and the whole, including the other fires, three hundred and eighty. Ten
tons colt 16 fchillings. The moulds are made of the country clay, and are hooped
with iron to render them more firm. Round the fhape for the mould hards of tow are
put mixed with tallow and clay, over which potter’s earth or clay mixed with fand.-
Five men are occupied in fafhioning the earth about the mould when cannon is cafting,
three knead the clay while two turn the fhape; the clay is put on crofswife : when
the mould is completed there are no more than three perfons employed in placing the
earth about it. It requires two days for the mould to get thoroughly dry ; for this
purpofe, when the wood is taken from it, coal and {mall wood are burnt within and
coal alone without, which is turned about as the mould dries. ‘The melting furnaces
are very large, built of granite, and the ftones are fupported by mafles of iron from
eleven to twelve feet long, in fhape of beams. ‘The two cannon of twenty-four and
four pounds are caft in eight minutes; in three hours time, notwithftanding the
pieces be yet red hot, the fand is removed in which the mould is placed. This is in a
wooden vat of eleven feet deep, and eight feet in diameter: conceive but an inftant
how violent the heat the men muft experience at the bottom of this vat, employed fo
near this burning mafs in removing and throwing out the fand: they are confequently
very quickly relieved.
In fix hours’ time the mafs has acquired a fufficient confiftence to allow of the piece
being withdrawn ; but it cannot be bored until after it has laid two or three days in the
open air. The firft opération then is to cut off the head of the cannon which is at
Jeaft a foot in length: this is done at firft with a round plate of fteel more than fix
lines in thicknefs ; the head is cut on three fides by turning this round plate, the piece
remaining motionlefs, which operation in a piece of twenty-four pounds takes up fix
hours. By that time the head holds but a very flender piece on the three fides ; iron
wedges are then ftruck into the part cut by a mallet of a lifpound in weight. The
more excellent the iron the greater the length of time before the head breaks off; it
has taken up four minutes when we have been prefent: after this the furplus at the
end of the cannon is cut off, and the end polifhed, which takes up two hours ; then the
boring begins at firft horizontally, the piece remaining immoveable: one man and a
boy only are employed in working the wheel, which forces forward and turns the
wedge in the piece ; this wedge or rather this bar is two inches thick, but the mouth
of the cannon is feven lines more, owing to the fteel end fitted to the bar, which ferves
as it turns to bore the gun, being one inchand a half. The firft hole is drilled, after-
wards it is bored perpendicularly, the borer turning and the piece being depreffed to
meet
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