《天工开物·中篇·陶埏》
每两碗灰末加以一碗红泥水后搅拌均匀，就形成釉料了。将它涂在坯上，烧出来的器皿就会呈现出漂亮的光泽。
每灰二碗参以红土泥水一碗，搅令极匀，蘸涂坯上，烧出自成光色。
Stirring fine ash with red clay water in a ratio of two bowls of ash to one bowl of water creates the glaze material. If this material is painted onto the board, the fired ware will have a beautiful luster.