By Leonardo, Windsor, RL 12349r.
Lifting heavy loads. This model in particular seems to have been created for lifting sections of the casting mold for the Sforza monument.
Tackle and crank-endless screw-gearing device.
Scaffolding shaped like a bridge with a tackle and four moving pulleys.
Size: the gantry crane was to be used for lifting the bronze horse and casting molds. From this data we can calculate a base of about 8 meters by 4 meters and about 7 meters in height.
Reconstruction: the top of the right rope is interrupted as if it had to be manually operated. It would be more logical to think that integrating this machine with a power reduction system symmetrical to the one on the left in order to use the same traction on both sides. An alternative is to anchor the rope firmly in the ground, and practice, therefore, traction only on one side; this could cause major operational difficulties for maintaining the movingpulley train and therefore the load would be left hanging.