Millrind

A millrind or simply rind is an iron support, usually four-armed or cross-shaped, for the turning ("runner") stone in a pair of millstones.

The rind is affixed to the top of the main shaft or spindle and supports the entire weight of the runner stone, which can be as much as several tons. The rind is necessary because the grain is fed through the runner stone's central hole, so the spindle cannot be inserted through it like a cartwheel on an axle.