(a) Boiled lin-seed oil will keep polished tools from rusting if it is allowed to dry on them. Common sperm oil will prevent them from rusting for a short period. A coat of copal varnish is frequently applied to polished tools exposed to the weather.
(6) Iron and steel goods of all descriptions are kept free from rust by the following: - Dissolve 1/2 oz. camphor in 1 lb. lard, take off the scum, and mix as much black-lead as will give the mixture an iron colour. Iron and steel and machinery of all kinds, rubbed over with this mixture, and left with it on for 24 hours, and then rubbed with a linen cloth, will keep clean for months. If the machinery is for exportation, it should be kept thickly coated with this during the voyage.
Take the first three ingredients in a pounded condition, and digest them by a regular heat till melted, then add the turpentine very gradually, stirring all the while. Rosin, 120 parts; sandarac, 180; gum lac, 60; essence of turpentine, 120. The mixture should be digested until solution, then add rectified alcohol, 180 parts. Filter through fine cloth or thick bibulous papers, and preserve in well-stoppered bottles or cases.
Immerse the article to be cleaned for a few minutes until all dirt and rust is taken off, in a strong solution of potassium cyanide, say about 1/2 oz. in a wine-glassful of water; take out and clean it with a toothbrush, with some paste composed of potassium cyanide, Castile soap, whiting, and water; these last are mixed in a paste about the consistence of thick cream.