139. Whenever practicable, the barrels should be arranged in double rows, with a passage-way between the rows, so that the marks on each barrel may be seen at a glance, and any barrel easily reached.
140. Besides being recorded in the magazine-book, each lot of powder should be inscribed on a ticket attached to the lot showing the entries and the issues.
141. Magazines should be opened and aired in clear, dry weather, the ventilators kept free, and no shrubbery or trees allowed to grow so near as to shade the building from the sun.
142. The moisture of a magazine may be absorbed by chloride of lime, or charcoal, suspended in an open box under the arch, and renewed from time to time. The use of quicklime is dangerous, and forbidden.
143. When powder is handled in powder-houses on shore, either for the purpose of inspection or preparation for delivery to ships, the baize-cloth is to be spread, and the people, before entering the magazine, must divest themselves of every metal implement, empty their pockets, that nothing likely to produce fire may escape detection, and put on the magazine dresses and slippers. The barrels must be opened only on the floor-cloth, and no metallic setter used in driving either copper or wooden hoops.
Powder-barrels should never be opened except when required for use, as grains of powder falling between the staves would prevent their being tightened. Samples must be taken from the bung.
144. The attention of the Inspectors of Ordnance and Commanders of vessels is called to the Regulations regarding the stowage and service of powder and loaded shells in Magazines and Shell-rooms, ashore and afloat, and to the precautions which must be observed by every one who enters, or approaches for the purpose of entering, any Magazine or Shell-room.
The former Regulations are modified so far as to dispense entirely with the use of slippers made of either India-rubber or woollen; and in lieu thereof, slippers made wholly of buckskin or cotton canvas will be used in future. In hot climates, or in warm weather generally, the naked feet are preferred.
The terrible effect of the explosion of a Magazine or Shell-room, ashore or on board ship, can only be imagined. To avert it, by every human precaution, is an imperative duty with every one. The Bureau therefore directs that the Inspectors of Ordnance on shore and the Commanders of all vessels afloat will cause the existing Powder Regulations to be read, and copies placed within the reach of every officer and man connected in the remotest degree with the service of the Magazine and Shell-rooms; and no officer or other person is to be continued in such service who cannot within a reasonable time answer clearly and fully any questions relating to the requirements of existing Powder Regulations as contained in these "Ordnance Instructions."
145. The powder in barrels should be turned from time to time, at least as often as every three months, and, being arranged as mentioned above, the oldest powder will be at all times accessible for first delivery without disturbing that of more recent manufacture.