gears and axles for translating the horizontal to vertical motion
for grinding. Initially, the entire structure of the post-mill had to
be rotated into the wind for use.
Figure 5.2 Early image of a post-mill from “Schembartbuch”, 1590–1640.
The technology evolved into the “tower-mill” and other
variations which still used a horizontal-axis but only required
rotation of the sails, wind-shaft and brake-wheel rather than the
entire tower structure. Moving into the 18th and 19th centuries,
various innovations in particular ...