Millrind

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

The rind is affixed to the top of the square-section 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.

The separation of the nether stone from the runner, controlling the fineness of the grind, was adjusted by the tenter mechanism: a screw jack to raise or lower the bearing carrying the base of spindle.

[2] The 16th century writer Bossewell characterized it as a symbol fit for judges and magistrates, who keep men on a straight course just as a millrind does with a runner stone.