A—UPRIGHT AXLE. B—BLOCK. C—ROOF BEAM. D—WHEEL.
E—TOOTHED-DRUM.
F—HORIZONTAL AXLE. G—DRUM COMPOSED OF RUNDLES. H—DRAWING ROPE.
I—POLE. K—UPRIGHT POSTS. L—CLEATS ON THE WHEEL.
wheel made of thick planks joined firmly together, and at its upper end a
toothed drum; this toothed drum turns another drum made of rundles, which
is on a horizontal axle. A winding-rope is wound around this latter axle,
which turns in iron bearings set in the beams. So that they may not fall, the
two workmen grasp with their hands a pole fixed to two upright posts, and
then pushing the cleats of the lower wheel backward with their feet, they
revolve the machine; as often as they have drawn up and emptied one
bucket full of excavated material, they turn the machine in the opposite
direction and draw out another.
F—HORIZONTAL AXLE. G—DRUM COMPOSED OF RUNDLES. H—DRAWING ROPE.
I—POLE. K—UPRIGHT POSTS. L—CLEATS ON THE WHEEL.
wheel made of thick planks joined firmly together, and at its upper end a
toothed drum; this toothed drum turns another drum made of rundles, which
is on a horizontal axle. A winding-rope is wound around this latter axle,
which turns in iron bearings set in the beams. So that they may not fall, the
two workmen grasp with their hands a pole fixed to two upright posts, and
then pushing the cleats of the lower wheel backward with their feet, they
revolve the machine; as often as they have drawn up and emptied one
bucket full of excavated material, they turn the machine in the opposite
direction and draw out another.
The fourth machine raises burdens once and a half as large again as the
two machines first explained. When it is made, sixteen beams are erected
each forty feet long, one foot thick and one foot wide, joined at the top with
clamps and widely separated at the bottom. The lower ends of all of
them are mortised into separate sills laid flat upon the ground; these sills
are five feet long, a foot and a half wide, and a foot thick. Each beam is also
connected with its sill by a post, whose upper end is mortised into the beam
two machines first explained. When it is made, sixteen beams are erected
each forty feet long, one foot thick and one foot wide, joined at the top with
clamps and widely separated at the bottom. The lower ends of all of
them are mortised into separate sills laid flat upon the ground; these sills
are five feet long, a foot and a half wide, and a foot thick. Each beam is also
connected with its sill by a post, whose upper end is mortised into the beam
zoom in
zoom out
zoom area
full page
page width
set mark
remove mark
get reference
digilib