The First Book of Mechanical Mathematical Instruments

FORM OF A NEW MACHINE, FOR UNLOADING SHIPS OR FOR LIFTING ANY KIND OF LOAD EASILY. 9

A detailed technical illustration of a mechanical crane designed for unloading ships. The device features a tall vertical post with a horizontal jib supported by a diagonal brace. A rope runs from a pulley at the end of the jib down to a bundle of cargo, which is suspended above a small boat moored at the water's edge. The base of the crane is sheltered by a circular, conical-roofed structure where a man is shown operating a large horizontal wheel or treadwheel to provide the lifting force. In the foreground, a man sits in a small boat loaded with cargo. The background depicts a mountainous landscape and a body of water.