Light slushing-oil will be used on the different parts of breech mechanisms, including the threads on the block and in the breech recess, in bores of guns, and on all other bright steel or iron surfaces of mobile and seacoast armament, as a preservative when the material is to remain unused for an appreciable length of time. The slushing-oil will replace synovial oil as a lubricant for cross-head guides, etc., which should be given a light coating only. The use of light slushing-oil as a lubricant on breech mechanisms, including the threads on the block and in the breech recess, is forbidden: synovial oil will be used exclusively for lubricating the different surfaces of breech mechanisms, including the threads on the block and in the breech recess, on translating-screws and rollers, and in all oil-holes and on gears, etc., of carriages. Number 4½ lubricant only will be used in grease-cups. If exposed to rain within thirty hours after its application, all surfaces should be carefully examined and recoated if necessary. It can be applied by means of paint-brushes known as sash-tools No. 6, issued for that purpose. Except in very cold weather it can be applied in a thin uniform coat by using the brush, as when painting. During cold weather it should be applied by stippling—i.e., lightly tapping the surface with the end of the brush—the brush being held perpendicular to the surface to be covered. It can be applied to the bores of guns by means of the slush-brush issued for the purpose. In cold weather it should be warmed before being applied to the bores of guns. In all cases it should be applied in a thin coat, since this is all that is necessary to give good protection.
This oil can be readily removed by the use of burlap or waste dipped in kerosene oil. Lye dissolved in hot water and used while hot will also remove it, but not as satisfactorily as kerosene oil. In order to reduce the amount of kerosene oil to be used for its removal, a thick coating of slushing-oil when present should first be removed with a scraper before applying the kerosene.
Water without the addition of lye or kerosene should be used for cleaning bores of guns after firing. They should be permitted to drain and then be wiped dry before applying the slushing-oil.
Before applying the slushing-oil to any surface it should be thoroughly cleaned so as to be free from rust, water, kerosene oil, lubricating-oil, etc., as their presence will cause rusting underneath the slushing-oil. If applied to an oiled surface, the slushing-oil has been found to run off when heated.
On account of the superior protection afforded by this material it will not be necessary to completely remove it for inspection purposes as frequently as has been found necessary with the protecting materials heretofore used. Its frequent removal from a limited area will serve as an indication of the protection which is being afforded.
III. Mortars will hereafter be dismounted from their carriages once every twelve months, and the trunnions and trunnion-beds thoroughly cleaned, including the oil-grooves in the trunnion-bed liners.
The counter-recoil springs will at the same time be dismounted, the old paint removed, and each spring given two coats of new paint. The spring should not be reassembled until the paint is dry.
By order of the Acting Secretary of War:
J. C. Bates,
Major-General, Acting Chief of Staff.