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Q. What is an automobile?

A. Any form of wheeled conveyance propelled by a prime mover carried by it as an integral part of its mechanism, is an automobile. This term, however, is usually applied only to those forms of selfpropelling vehicles designed to replace pleasure vehicles or trucks formerly drawn by horses. The steam roller, gas traction engine, steam locomotive, and various other forms of self-propelling machinery are not included in this classification.

Q. Name the three principal types of automobile.

A. Three forms of automobiles have been generally used, these being termed steam, electric or gasoline, according to the nature of their power plant. Forms of cars propelled by liquid air or compressed air have been tried but found unsatisfactory.

Q. What are the advantages of steam power?

A. The most important advantage of the steam engine as an automobile power plant, is that it is extremely flexible and is capable of delivering power which augments directly as the amount of steam admitted to the cylinders increases. All functions of the starting, stopping, reversing and speed changing may be obtained directly by throttle control. When more power is needed, as in hill climbing, the throttle is opened wider and more steam is admitted from the boiler to the cylinders, thus directly increasing the engine power. The steam automobile has disadvantages that offset the good features. Among these may be mentioned difficulty in starting promptly, as firing up is necessary in order to generate sufficient steam to run the engine; use of naked flame under the boiler which introduces an undesirable element of danger from fire; constant attention to air, water, and fuel pumps; necessity of maintaining proper water level in boiler at all times; frequent replenishing of water supply which lasts but 20 miles as a rule, and excessive use of fuel. It will be seen that while the steam car is simpler to control than that propelled by gas power, there are so many things to watch that it requires constant attention on the part of the operator to keep the car running as it should.

Q. What are the advantages of the electric car?

The electric motor offers many advantages as a source of power for automobile propulsion. It is flexible and as easily controlled as a steam engine, because the electric energy used is drawn from an exterior source or storage battery just as the steam is drawn from a container or boiler where it is generated and stored under pressure. The power of the electric motor may be varied by altering the amount of electricity supplied to the windings. The electric automobile can be started, stopped, reversed, and various changes of speed obtained by the simple movement of a controller lever. The electric automobile is quiet, clean, easy riding, and especially adapted for use of women and children.

It is lacking in capacity, however, and has a well defined radius of action which is determined by the endurance of the storage battery which supplies the electricity. After an electric automobile is operated for a period equal to traveling a distance of 60 to 100 miles, depending upon the type, the batteries must be re-charged. This means that the electric automobile can only be used where proper charging facilities are available, which practically confines its use to the larger cities and towns and their suburbs. The electric automobile is not suitable for touring, and if run at its maximum speed for any length of time, the batteries are soon exhausted.

Q. What are the advantages of gas power?

A. The internal combustion or gasoline engine, as it is commonly called, because of the fuel generally used, has some disadvantages when compared to steam and electric power, but its many marked advantages make it superior to either of these types. A gas engine may be easily started by a simple quarter turn of the starting crank when in proper condition, and is as easily controlled after it is set in motion as either the steam or electric motor. Modern gasoline automobile engines have great flexibility, and have a range of speed from 150 to 1,200 or more revolutions per minute, by simple movement of the spark and throttle control levers.

Once the gasoline engine is set in motion, it requires no more attention from the operator, and it will continue to run as long as the fuel supply, lubricating oil, and electrical ignition will hold out. Its range or touring radius is not limited by conditions which make it necessary to frequently replenish the supply of water, as is the case with the steam engine, and it is independent of the central charging station on which the electric automobile depends. It will carry fuel enough in a tank of small size so it is possible to go several hundred miles without a stop, and then this is only a stop of a few minutes duration or just long enough to refill the gasoline and oil tanks.

The internal combustion motor is the most economical form to operate, and as a rule, automobiles equipped with this form of power require less attention than either steam or electric automobiles. Some of the disadvantages advanced against the gasoline power plant are: lack of overload capacity which necessitates the use of change speed gears; inability to reverse engine, which means that reversing gearing is necessary to allow the automobile to run backward; inability to start engine under load, which means that a separate clutching mechanism is needed so the motor may be started independent of the vehicle and to permit it to run fast enough to develop its full power before the car is started. Electric motors and steam engines start as soon as the automobile to which they are fitted does, and as no clutch is necessary, they may be directly connected to the driving wheels by some form of positive gearing. Owing to its lack of overload capacity, reduction gearing must be used whenever a gasoline car is made to climb a steep hill, whereas the power of the electric or steam motor may be increased by permitting more energy to flow from the container where it is stored under pressure to the motor, thus no change speed gears are necessary on these types of vehicles. . The disadvantages mentioned are more apparent than real, as with the highly developed form of gasoline engines of the present day, there is no need of constant gear changing or speed

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Fig. 1.-Chassis of the Pleasure Car Type Fitted With Various Forms of Delivery Bodies. A-Stake Platform Body. B–Wire Side

Delivery. C—Panel Side Delivery.

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