《天工开物·上篇·粹精》
稻谷去掉谷壳用的是砻，去掉糠皮用的是舂或者碾；但是用水碓来舂，也就同时起了砻的作用。
凡稻去壳用砻，去膜用舂、用碾。然水碓主舂，则兼并砻功。
The rice used to husk the grain is a grinding machine, and the rice used to remove the bran is a pounder or a grinder; but when using a water mill to pound, it also acts as a grinding machine.