Flexibility.
—While the brakes are most useful in the prevention of accidents, it frequently happens that a quick pick-up is also important. In crossing the street ahead of a car coming at right angles, for instance, there may be no time to stop, no chance to turn, the only thing that can be done is to “give her gas” and shoot ahead at full speed. A flexible engine with ability to change quickly from fast to slow and from slow to fast velocities will in the hands of an expert driver prevent many an accident.