nectors are loose when pushed together, the contact will be poor. Spread the connector posts slightly so that they will slide in their sockets snugly. If Ediswan type are used, and plunger springs in connector do not operate, replace the connector with a perfect one.

The storage battery is made up of several hard rubber cells or containers for the active plates and liquid electrolyte. The whole is surrounded by a wood casing for mechanical protection and ease in handling. Each individual cell is provided with a screw cap for inspection and the addition of electrolyte or distilled water when necessary (See Fig. 73 and Fig. 74). The electrolyte must at all times cover the tops of the plates at least one-quarter inch. Insufficient electrolyte will result in warped or buckled plates, and an accumulation of sediment at the bottom of the cells. The battery will be ruined in a short time if the tops of the plates are not kept covered. Each cell must be inspected at least once every week in summer and once every two weeks in winter. All screw caps must be removed and distilled water added to each cell to make up for the natural evaporation. If distilled water cannot be had use clean rain water which has not come in contact with metal or cement.

Never add acid to the cells of the battery. If part or all of the electrolyte has been lost through accidental spilling or leakage get full instructions and advice from the maker. An hydrometer, arranged with a rubber bulb to draw a portion of the electrolyte from each cell, furnishes the best indication of the condition of the battery. The hydrometer shows the specific gravity of the electrolyte, which for a fully charged cell should be 1280 on a specific gravity scale. If the car is out of service for a considerable length of time, as when laid up for the winter, it is necessary to charge the battery at regular intervals. This may be done by running the engine at a car speed of twenty miles per hour for at least one hour every two weeks. If the car is to be stored, and it is not convenient to charge as above, the battery should be removed from the car and placed in a reliable garage to be properly taken care of.

If your battery is arranged with terminal posts for the wiring connections these must be examined occasionally to see that they are clean and free from sulphate. The thorough application of a small amount of vaseline at the metal connections to the battery

posts will prevent sulphating and consequent corrosion and poor electrical contact at these points. If the electrolyte leaks from the joints, bottom, or wood sides of the battery case, one or more of the hard rubber cells are cracked or broken. The battery must be returned to the factory for repairs or replacement. The metal battery box must be thoroughly wiped out with a cloth saturated with ammonia to neutralize the acid and prevent corrosion. The top

of the battery must be kept clean and dry to prevent a leakage of current between the terminals. See that the battery is held securely in its metal box or other container. If necessary pack tightly with waste to prevent the battery shaking about from jolting of the car. Tools, other metal articles, or anything of value should not be placed near the battery as the acid fumes will corrode and destroy metal, cloth and like material. Make certain that the battery terminals cannot touch the cover of the metal battery box. A thin sheet of wood fiber fitted inside the cover of the battery box will prevent short circuits or grounds from this cause. It must be remembered that the efficiency of any storage battery decreases with drop in temperature and it is only about 50 per cent. efficient at zero temperature. For this reason the demand for current should be kept as low as possible in cold weather and lamps turned off when not needed.

The user of any electrical starting and lighting system will avoid trouble and expense by the observation of the following instructions:

Don't replace worn-out brushes with any others than those supplied by the manufacturer.

Don't put oil or grease on the commutator of the generator or motor. No lubrication is wanted there.

Don't turn the hose on the generator or motor when washing your car.

Don't tighten up on the silent chain drive unless the slack becomes excessive from stretching. The chain must be run with a reasonable amount of slack to prevent noise and wear.

Don't fail to lubricate the silent chain drive at frequent inter-` vals. Noise will be eliminated and wear reduced. Keep the chain and sprockets clean, and free from dirt and gravel.

Don't run your car, if for any reason the battery is disconnected from the circuit, unless you have disconnected the chain driving the generator, or the generator itself has been removed.

Don't attempt to propel car with starter. Such "stunts" are interesting, but expensive. Gasoline is for that purpose.

Don't attempt to make adjustments of any kind in the circuit breaker.

Don't fuss with the system when it is operating properly.

Hints For Locating Delco Trouble.-1. If starter, lights and horn all fail, the trouble is in the storage battery or its connections, such as a loose or corroded connection or a broken battery jar. 2. If the lights, horn and ignition are all O. K., but the starter fails to crank the trouble is in the motor generator, such as dirt or grease on the motor commutator, or the motor brush not dropping on the commutator. 3. If the starter fails to crank or cranks very slowly, and the lights go out or get very dim while cranking, it indicates a loose or corroded connection on the storage battery, or a nearly depleted storage battery. 4. If the motor fires properly on the "M" button, but not on the "B" button, the trouble must be in the wiring between the dry cells or the wires leading from the dry cells to the combination switch, or depleted dry cells. If the igni tion works O. K. on the "B" button and not on the "M" button, the trouble must be in the leads running from the storage battery to the motor generator, or the lead running from the rear terminal on the generator to the combination switch, or in the storage battery itself, or its connection to the frame of the car. 5. If both systems of ignition fail, and the supply of current from both the storage battery and dry cells is O. K., the trouble must be in the coil, resistance unit, timer contacts or condenser. This is apparent from the fact that these work in the same capacity for each system of ignition.

Never run the car with the storage battery disconnected, or while it is off the car. Very serious damage to the motor-generator may result from such action.

Never remove any electrical apparatus from the car or make any adjustments without first disconnecting the storage battery. This can be done most conveniently by removing the ground con