Machine for lifting columns

Working on systems drawn by Francesco di Giorgio Martini and other engineers, Leonardo refines this mobile winch in order to transport and lift columns and obelisks.

The base of the column rests on a trolley that can slide horizontally. A wheel turned by a crank moves the trolley and the large worm screw. The screw, positioned at the centre of the column, pushes the top extremity upwards placing the column vertically.
Codex Atlanticus, sheet 818 about 1495