Leonardo da Vinci Sketches the Design for a Giant Crossbow
Leonardo’s project for a giant crossbow is found in a number of sheets in the Codex Atlanticus and Fol 149r shows the most well-defined and complete drawing.
The effort put into the design of the components indicates that he was striving to realise it as a workable weapon. The structure is huge; its dimensions can be judged when comparing the machine to the drawing of a man who is operating it.
We usually think of Leonardo as an artist. However, it was his skill as a military engineer that was largely responsible for securing his employment in 15th century Milan.
Around 1486, Leonardo drew several designs for a giant crossbow. The figure atop the machine gives an indication of scale. The weapon was cranked with winding gears. It had two different firing mechanisms - the simplest of which involved releasing a holding pin by striking it with a mallet.