page 123 note † It could be made quite complete by substituting “drawn from the point” for the last four words, which as they stand do not indicate the sense in which the diagonal is to be taken. In this connection I should like to suggest that the type of enunciation of such theorems in which a lettered diagram (actual or imaginary) is referred to, is preferable for clearness and brevity combined : e.g. If a moving point possess simultaneously two velocities represented in magnitude and direction by OA, OB, two lines drawn from a point O, then the resultant velocity is represented in direction and magnitude on the same scale by the diagonal OC of the completed parallelogram OACB. The late Professor Casey adopted this type of enunciation in his Euclid.