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SYNOPSIS OF LESSONS
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?
A. Any form of wheeled conveyanice propelled by a prime mover carried by it as an integral part of its mechanism, is an automobile. This term, however, is üsually 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