To 6 qts. soft water put in corrosive sublimate, 1 oz.; common salt, 2 handfuls; when dissolved, it is ready for use. The first gives toughness to the steel, while the latter gives the hardness. Be careful with this preparation, as it is a dangerous poison.

Another

Salt, ½ tea-cup; saltpetre, ½ oz., alum, pulverized, 1 teaspoon; soft water, 1 gallon; never heat over a cherry red, nor draw any temper.

Another

Saltpetre, sal-ammoniac and alum, of each 2 oz.; salt, 1½ lbs.; water, 3 gallons, and draw no temper.

Another

Saltpetre and alum each, 2 oz.; sal-ammoniac, ½ oz.; salt, 1½ lbs.; soft water, 2 gallons. Heat to a cherry red, and plunge in, drawing no temper.

Another

Water, 3 gallons; salt, 2 qts.; sal-ammoniac and saltpetre, of each 2 oz.; ashes from white-ash bark, 1 shovel, which causes the steel to scale white and smooth as silver. Do not hammer too cold, to avoid flaws; do not heat too high, which opens the pores of the steel; and do not heat more than one or two inches of the steel at a time while tempering, if you wish the hardness and toughness of the steel to be of the first quality.