Crane (machine)
The crane is a wooden construction crane that was used to move heavy loads.
The crane had a climbing wheel ( impeller ) that a person climbed into to drive the horizontal shaft of the wheel. The shaft rested on a suspended column structure that was attached to the upwardly tapering rotatable stand. The stand was given the necessary stability by means of a braced base. The beak (crane arm in the form of a single-stile ladder) was mounted on the stand at an angle of about 40 degrees and braced. A band (rope) attached to the shaft led up over the crane arm to the pulley (made of brass), which led the rope to the vertical on the attached crane hook (and back again).
If you wanted to swivel the crane's boom, you put a rotating boom through the running wheel and levered it around your foot in the desired position.
source
- The workshops of today's arts . The carpenter. Hall 1764.