4. Inspect each cell of the battery carefully at regular intervals. 5. If any low cells develop do not delay in bringing them back to condition. 6. Do not allow the sediment to get up to the plates. 7. Do not allow impurities, either solid or liquid, to get into or remain in the cells. 8. Have the battery room well ventilated, especially while charging. 9. Never bring an exposed flame into the battery room during or shortly after the gassing period of a charge. 10. Keep the floor and other parts of the battery room clean and dry. 11. Keep the iron, copper, or other metal work about the battery room free from corrosion. 12. Keep all connections clean and tight. 13. Post a copy of these condensed instructions in a conspicuous place. APPENDIX NO. 4. SUBMARINE MINE CABLE. Submarine mine cable is shipped on reels having an outer sheathing for protection in transit, with at least 12 feet of both ends of the cable brought out and coiled on the head of the reel for test purposes. If the cable is not for immediate use, it should be moved to the cable tank, and by means of the overhead trolley and cable tongs put in its position in the tank, the two ends being properly tagged and firmly fixed so as to allow it to be tested. In arranging the multiple cable in the tanks that which is to be used first should be most readily accessible. The cable tank should be provided with a cover to keep it clean, as well as to lessen as much as possible variations of temperature. Enough clean water to cover by several inches the outer sheathing of the cable reels should be kept in the tanks, but in climates where the water in the cable tanks would normally freeze to a depth exceeding 2 feet, the water should be let out of the tanks before ice begins to form and not again admitted until the following spring. In localities where the tanks may become a breeding place for mosquitoes, as a preventive measure, salt water from the ocean or bay should, when practicable, be used for filling the tanks, or where it is necessary to use fresh water sufficient salt should be added to produce a 3 per cent solution. No oil or kerosene should be used in the tanks. The methods of recording tests and of classifying and transferring submarine mine cable are prescribed by orders from the War Department. The tests of submarine mine cable at posts will consist in determining the insulation and conductor resistances.