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CHAPTER X
THE PETROL CAR
I. TRANSMISSION
By Henry Sturmey
This is a wide subject, and to be properly and thoroughly dealt with requires much more space than has been placed at my disposal, so that I shall simply endeavour to deal broadly with the principles of the best known types. Next to the engine itself the construction of the transmission gear is the most important thing about an autocar; for as this portion of the machine is the medium through which the power is conveyed from the engine to the wheels, it does not require an intimate knowledge of mechanics to perceive that bad design and undue friction here may make a very material difference in the running and speed of the car. As a matter of fact the whole power of the engine is never available for the work of turning the wheels of the car, a certain portion of it always being absorbed in the work of driving the gear; indeed, it is not too much to say that in some instances—as has indeed been proved by actual tests—fully one half of the power developed by the engine is thus lost between the motor and the wheels. Consequently high efficiency in the transmission arrangements will mean greater economy in work, as well as better hill-climbing and speed results from the same engine, than would have been the case had a more faulty system been adopted. Broadly speaking, it may be said that the old adage 'simplicity is a virtue' holds particularly good in this connection, and it may be taken as an axiom that—all other things being
