1and its lower end mortised into
the sill; these posts are four feet long, one
foot thick, and one foot wide. Thus a circular area is made, the diameter of
which is fifty feet; in the middle of this area a hole is sunk to a depth of ten
feet, and rammed down tight, and in order to give it sufficient firmness, it is
strengthened with contiguous small timbers, through which pins are driven,
for by them the earth around the hole is held so that it cannot fall in. In
the bottom of the hole is planted a sill, three or four feet long and a foot and a
half thick and wide; in order that it may remain fixed, it is set into the small
timbers; in the middle of it is a steel socket in which the pivot of the axle turns.
In like manner a timber is mortised into two of the large beams, at the top
beneath the clamps; this has an iron bearing in which the other iron journal of
the axle revolves. Every axle used in mining, to speak of them once for all,
has two iron journals, rounded off on all sides, one fixed with keys in the centre
of each end. That part of this journal which is fixed to the end
of the axle is as broad as the end itself and a digit thick; that which
projects beyond the axle is round and a palm thick, or thicker if necessity
requires; the ends of each miner's axle are encircled and bound by an
iron band to hold the journal more securely. The axle of this machine,
except at the ends, is square, and is forty feet long, a foot and a half thick
and wide. Mortised and clamped into the axle above the lower end are the
ends of four inclined beams; their outer ends support two double crossÂ
beams similarly mortised into them; the inclined beams are eighteen feet
long, three palms thick, and five wide. The two cross-beams are fixed to
the axle and held together by wooden keys so that they will not separate,
and they are twenty-four feet long. Next, there is a drum which is made of
three wheels, of which the middle one is seven feet distant from the upper
one and from the lower one; the wheels have four spokes which are
supported by the same number of inclined braces, the lower ends of which
are joined together round the axle by a clamp; one end of each spoke is
mortised into the axle and the other into the rim. There are rundles all
round the wheels, reaching from the rim of the lowest one to the rim of the
middle one, and likewise from the rim of the middle wheel to the rim of the top
one; around these rundles are wound the drawing-ropes, one between the lowest
wheel and the middle one, the other between the middle and top wheels.
The whole of this construction is shaped like a cone, and is covered with a
shingle roof, with the exception of that square part which faces the shaft.
Then cross-beams, mortised at both ends, connect a double row of upright
posts; all of these are eighteen feet long, but the posts are one foot thick
and one foot wide, and the cross-beams are three palms thick and wide.
There are sixteen posts and eight cross-beams, and upon these cross-beams
are laid two timbers a foot wide and three palms thick, hollowed out to a
width of half a foot and to a depth of five digits; the one is laid upon the
upper cross-beams and the other upon the lower; each is long enough to
reach nearly from the drum of the whim to the shaft. Near the same drum
each timber has a small round wooden roller six digits thick, whose ends are
foot thick, and one foot wide. Thus a circular area is made, the diameter of
which is fifty feet; in the middle of this area a hole is sunk to a depth of ten
feet, and rammed down tight, and in order to give it sufficient firmness, it is
strengthened with contiguous small timbers, through which pins are driven,
for by them the earth around the hole is held so that it cannot fall in. In
the bottom of the hole is planted a sill, three or four feet long and a foot and a
half thick and wide; in order that it may remain fixed, it is set into the small
timbers; in the middle of it is a steel socket in which the pivot of the axle turns.
In like manner a timber is mortised into two of the large beams, at the top
beneath the clamps; this has an iron bearing in which the other iron journal of
the axle revolves. Every axle used in mining, to speak of them once for all,
has two iron journals, rounded off on all sides, one fixed with keys in the centre
of each end. That part of this journal which is fixed to the end
of the axle is as broad as the end itself and a digit thick; that which
projects beyond the axle is round and a palm thick, or thicker if necessity
requires; the ends of each miner's axle are encircled and bound by an
iron band to hold the journal more securely. The axle of this machine,
except at the ends, is square, and is forty feet long, a foot and a half thick
and wide. Mortised and clamped into the axle above the lower end are the
ends of four inclined beams; their outer ends support two double crossÂ
beams similarly mortised into them; the inclined beams are eighteen feet
long, three palms thick, and five wide. The two cross-beams are fixed to
the axle and held together by wooden keys so that they will not separate,
and they are twenty-four feet long. Next, there is a drum which is made of
three wheels, of which the middle one is seven feet distant from the upper
one and from the lower one; the wheels have four spokes which are
supported by the same number of inclined braces, the lower ends of which
are joined together round the axle by a clamp; one end of each spoke is
mortised into the axle and the other into the rim. There are rundles all
round the wheels, reaching from the rim of the lowest one to the rim of the
middle one, and likewise from the rim of the middle wheel to the rim of the top
one; around these rundles are wound the drawing-ropes, one between the lowest
wheel and the middle one, the other between the middle and top wheels.
The whole of this construction is shaped like a cone, and is covered with a
shingle roof, with the exception of that square part which faces the shaft.
Then cross-beams, mortised at both ends, connect a double row of upright
posts; all of these are eighteen feet long, but the posts are one foot thick
and one foot wide, and the cross-beams are three palms thick and wide.
There are sixteen posts and eight cross-beams, and upon these cross-beams
are laid two timbers a foot wide and three palms thick, hollowed out to a
width of half a foot and to a depth of five digits; the one is laid upon the
upper cross-beams and the other upon the lower; each is long enough to
reach nearly from the drum of the whim to the shaft. Near the same drum
each timber has a small round wooden roller six digits thick, whose ends are
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