Folio 12

This page consists entirely of mechanical studies with no accompanying text. The primary drawing shows a complex mechanism mounted on a vertical wooden beam. Leonardo used pen and brown ink over a preparatory sketch in red chalk.

A detailed study of a mechanical device involves a vertical shaft and horizontal transmission arms. This drawing explores the transmission of motion or a lifting mechanism centered on a vertical post. To the left, a bucket or weight hangs from a pivoted arm. The central hub appears to feature a cog or gear. The drawing is executed in pen and brown ink over a preparatory sketch in red chalk, also known as sanguine.

A faint red chalk underdrawing shows a wheel or circular frame. This was likely a preliminary concept for the more finished ink drawing on the same page.

A small, rapid sketch in red chalk depicts a mechanical part. This is likely a lever or trigger mechanism related to the main study.

mechanics (meccanica), gear (ingranaggio), vertical shaft (albero verticale), counterweight (contrappeso)