=Sediment.=—The accumulation of sediment in the bottom of the jars must be watched and not allowed under any circumstances to get up to the plates; if this occurs, rapid deterioration will result. To remove the sediment, the simplest way, if the cells are small, is to lift the elements out after the battery has been fully charged, draw off the electrolyte, and then dump the sediment, and clean the jar with water, getting the elements back and covered with electrolyte again as quickly as possible, so that there will be no chance of the plates drying out. Electrolyte, not water, will be required to complete the filling of the cells, the specific gravity being adjusted to standard (1.210 at the end of charge). =Evaporation.=—Do not allow the surface of the electrolyte to get down to the top of the plates; keep it at its proper level (one-half inch to three-fourths inch above the top of the plates) by the addition of pure water, which should be added at the beginning of a charge, preferably the overcharge. It will not be necessary to add electrolyte except at long intervals or when cleaning, as noted above. Electrolyte added to replace loss should be of specific gravity 1.210. =Battery used but occasionally.=—If the battery is to be used at infrequent periods, it should be given a “freshening” charge every two weeks. =Putting the battery out of commission.=—If it is thought best to put the battery out of commission for a time, then it must be treated as follows: After thoroughly charging, syphon off the electrolyte (which may be used again) into convenient receptacles, preferably carboys which have been previously cleaned and have never been used for other kinds of acid, and as each cell becomes empty immediately fill it with fresh, pure water. When water is in all the cells allow them to stand 12 to 15 hours, then draw off the water; the battery may then stand without further attention until it is again to be put into service; then proceed as in the case of the initial charge, as described above. If for any reason any cell becomes discharged before the others, it should be cut out on discharge and worked up to normal before being used. Should the battery sulphate, charge and discharge frequently, not using less than one-half normal rate at any time and increasing to full rate as the plates show signs of recuperation; keep the temperature of the cells below 100° F. Frequent exercise will clear the plates in a badly sulphated battery. Keep careful records of all charging voltages, specific gravities, and troubles with the cells. The following is a recapitulation of the important points in operating a storage battery: CONDENSED INSTRUCTIONS. 1. Excessive charging must be avoided. A battery should not be undercharged, overdischarged, or allowed to stand completely discharged. 2. Keep the electrolyte at the proper height above the top of the plates. 3. The daily and weekly readings should be regularly and accurately taken and recorded.