. . . "The gears or other components make the three shafts rotate in such a way that $\backslash \backslash scriptstyle\; a=pb+qc$, where $\backslash \backslash scriptstyle\; a$, $\backslash \backslash scriptstyle\; b$, and $\backslash \backslash scriptstyle\; c$ are the angular velocities of the three shafts, and $\backslash \backslash scriptstyle\; p$ and $\backslash \backslash scriptstyle\; q$ are constants." .