1covered with iron bands and
revolve in iron rings.
Each timber also has a
wooden pulley, which together with its iron axle revolves in holes in the
timber. These pulleys are hollowed out all round, in order that the drawing
rope may not slip out of them, and thus each rope is drawn tight and turns
over its own roller and its own pulley. The iron hook of each rope is engaged
with the bale of the bucket. Further, with regard to the double cross
beams which are mortised to the lower part of the main axle, to each end
of them there is mortised a small piece of wood four feet long. These appear
to hang from the double cross-beams, and a short wooden block is fixed to the
lower part of them, on which a driver sits. Each of these blocks has an iron
clavis which holds a chain, and that in turn a pole-bar. In this way it is
possible for two horses to draw this whim, now this way and now that; turn
by turn one bucket is drawn out of the shaft full and another is let down
into it empty; if, indeed, the shaft is very deep four horses turn the whim.
When a bucket has been drawn up, whether filled with dry or wet materials,
it must be emptied, and a workman inserts a grappling hook and overturns
it; this hook hangs on a chain made of three or four links, fixed to a timber.
wooden pulley, which together with its iron axle revolves in holes in the
timber. These pulleys are hollowed out all round, in order that the drawing
rope may not slip out of them, and thus each rope is drawn tight and turns
over its own roller and its own pulley. The iron hook of each rope is engaged
with the bale of the bucket. Further, with regard to the double cross
beams which are mortised to the lower part of the main axle, to each end
of them there is mortised a small piece of wood four feet long. These appear
to hang from the double cross-beams, and a short wooden block is fixed to the
lower part of them, on which a driver sits. Each of these blocks has an iron
clavis which holds a chain, and that in turn a pole-bar. In this way it is
possible for two horses to draw this whim, now this way and now that; turn
by turn one bucket is drawn out of the shaft full and another is let down
into it empty; if, indeed, the shaft is very deep four horses turn the whim.
When a bucket has been drawn up, whether filled with dry or wet materials,
it must be emptied, and a workman inserts a grappling hook and overturns
it; this hook hangs on a chain made of three or four links, fixed to a timber.
The fifth machine is partly like the whim, and partly like the third rag
and chain pump, which draws water by balls when turned by horse power,
as I will explain a little later. Like this pump, it is turned by horse
power and has two axles, namely, an upright one—about whose lower end,
which decends into an underground chamber, there is a toothed drum—and a
horizontal one, around which there is a drum made of rundles. It has indeed
two drums around its horizontal axle, similar to those of the big machine, but
smaller, because it draws buckets from a shaft almost two hundred and forty
feet deep. One drum is made of hubs to which cleats are fixed, and
the other is made of rundles; and near the latter is a wheel two
feet deep, measured on all sides around the axle, and one foot wide; and
against this impinges a brake,10 which holds the whim when occasion demands
that it be stopped. This is necessary when the hide buckets are emptied
after being drawn up full of rock fragments or earth, or as often as water
is poured out of buckets similarly drawn up; for this machine not only
raises dry loads, but also wet ones, just like the other four machines which
I have already described. By this also, timbers fastened on to its winding
chain are let down into a shaft. The brake is made of a piece of wood one
foot thick and half a foot long, projecting from a timber that is suspended
by a chain from one end of a beam which oscillates on an iron pin, this in
turn being supported in the claws of an upright post; and from the other end
of this oscillating beam a long timber is suspended by a chain, and from this
long timber again a short beam is suspended. A workman sits on the short
beam when the machine needs to be stopped, and lowers it; he then inserts
a plank or small stick so that the two timbers are held down and cannot be
raised. In this way the brake is raised, and seizing the drum, presses it
so tightly that sparks often fly from it; the suspended timber to which
the short beam is attached, has several holes in which the chain is
and chain pump, which draws water by balls when turned by horse power,
as I will explain a little later. Like this pump, it is turned by horse
power and has two axles, namely, an upright one—about whose lower end,
which decends into an underground chamber, there is a toothed drum—and a
horizontal one, around which there is a drum made of rundles. It has indeed
two drums around its horizontal axle, similar to those of the big machine, but
smaller, because it draws buckets from a shaft almost two hundred and forty
feet deep. One drum is made of hubs to which cleats are fixed, and
the other is made of rundles; and near the latter is a wheel two
feet deep, measured on all sides around the axle, and one foot wide; and
against this impinges a brake,10 which holds the whim when occasion demands
that it be stopped. This is necessary when the hide buckets are emptied
after being drawn up full of rock fragments or earth, or as often as water
is poured out of buckets similarly drawn up; for this machine not only
raises dry loads, but also wet ones, just like the other four machines which
I have already described. By this also, timbers fastened on to its winding
chain are let down into a shaft. The brake is made of a piece of wood one
foot thick and half a foot long, projecting from a timber that is suspended
by a chain from one end of a beam which oscillates on an iron pin, this in
turn being supported in the claws of an upright post; and from the other end
of this oscillating beam a long timber is suspended by a chain, and from this
long timber again a short beam is suspended. A workman sits on the short
beam when the machine needs to be stopped, and lowers it; he then inserts
a plank or small stick so that the two timbers are held down and cannot be
raised. In this way the brake is raised, and seizing the drum, presses it
so tightly that sparks often fly from it; the suspended timber to which
the short beam is attached, has several holes in which the chain is
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