Make a mixture, one part emery, and three parts crocus martis, in very fine powder. Mix them to a thick paste, with a little lard or sweet oil. Have your knife-board covered with a thick buff-leather. Spread this paste on your leather, to about the thickness of a quarter-dollar. Rub your knives in it, and it will make them much sharper and brighter, and will wear them out less, than the common method of cleaning with brick-dust, on a bare board.