The red dye fastest to light, washing, etc., is alizarin or Turkey red. For wool, mordant with a bath of sulphate of alumina and cream of tartar, and dye in a bath of alizarin paste and acetate of lime. For 100 lb. of wool use 10 lb. of sulphate of alumina, 5 lb. of cream of tartar, 10 lb. of alizarin paste, and 5 lb. of acetate of lime. The dyeing of cotton is a more complicated process.