Overdrift

The overdrift method in smock mills may be seen at Punnetts Town, and the underdrift at Shipley.

Source: wiktionary

In an overdrift mill this gear is mounted on the quant, in an underdrift mill on the stone spindle.

Source: wiktionary

For cleanliness, experienced millers prefer an 'overdrift' mill (as, indeed windmills should be, for lightness and efficiency of driving gears), because underdrift gearing becomes very dirty and clogged with a compound of meal dust and grease, besides being generally inaccessible for repairs and adjustments.

Source: wiktionary

Green be those downs and dells above the sea, Smooth-green for ever, by the plough unhurt, Nor overdrifted by their neighbouring sands, Where first I saw you ;

Source: wiktionary