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27—Methods of Speed Changing Outlined...
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The writer wishes to acknowledge his indebtedness to a number of the leading automobile and parts manufacturers who furnished instruction books and photographs from which a number of the illustrations used were taken and which also offered valuable suggestions for treatment of this subject. While in nearly all cases credit is given in connection with illustration to the user or maker of the construction shown, general credit is due to the following manufacturers whose co-operation has made the production of a complete and authoritative work possible:
Packard Motor Car Co., Detroit, Mich.
THE MODERN GASOLINE AUTOMOBILE AND ITS
Q. What is an automobile?
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?
A. 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