motor unit

The flexibility of the gasolene-motor unit is indeed astounding.

The upshot of it was that somebody reported him, and the officer in command of his "motor-unit" read him a stern lecture.

He wrote a letter to the officer in command of his motor-unit, telling what had happened to him, and couldn't it be arranged?

For the moment we have permitted ourselves to drift away from the gasolene-motor unit upon the railroad track.