In a recent number of the American Mathematical Monthly (December 1914), Professor E. V. Huntington calls attention to the inconclusive, and in some cases erroneous, discussion of the uniplanar motion of a rigid body as it is presented in the more elementary books on mechanics. In the simpler problems considered the solution is usually found by use of the rule that the rate of change of moment of momentum about some convenient point is equal to the torque or turning moment about the same point. In many cases there is no difficulty choosing this convenient point; but apparently there is confusion as to the points which can be legitimately chosen.