First grease the articles well; then, after a few-days, rub them with a rag charged with ammonia. If the rust spots persist, add a few drops of hydrochloric acid to the ammonia, rub and wipe off at once. Next rinse with water, dry, and polish with tripoli.

Removal of Rust

To take off the rust from small articles which glass or emery paper would bite too deeply, the ink-erasing rubber used in business offices may be employed. By beveling it, or cutting it to a point as needful, it can be introduced into the smallest cavities and windings, and a, perfect cleaning be effected.

To Remove Rust from Instruments

I

Lay the instruments over night in a saturated solution of chloride of tin. The rust spots will disappear through reduction. Upon withdrawal from the solution the instruments are rinsed with water, placed in a hot soda-soap solution, and dried. Cleaning with absolute alcohol and polishing chalk may also follow.

II

Make a solution of 1 part of kerosene in 200 parts of benzine or carbon tetrachloride, and dip the instruments, which have been dried by leaving them in heated air, in this, moving their parts, if movable, as in forceps and scissors, about under the liquid, so that it may enter all the crevices. Next lay the instruments on a plate in a dry room, so that the benzine can evaporate. Needles are simply thrown in the paraffine solution, and taken out with tongs or tweezers, after which they are allowed to dry on a plate.

III

Pour olive oil on the rust spots and leave for several days; then rub with emery or tripoli, without wiping off the oil as far as possible, or always bringing it back on the spot. Afterwards remove the emery and the oil with a rag, rub again with emery soaked with vinegar, and finally with fine plumbago on a piece of chamois skin.

To Preserve Steel from Rust

To preserve steel from rust dissolve 1 part caoutchouc and 16 parts turpentine with a gentle heat, then add 8 parts boiled oil, and mix by bringing them to the heat of boiling water. Apply to the steel with a brush, the same as varnish. It can be removed again with a cloth soaked in turpentine.