Fig. 87 shows the data of Fig. 85 and Fig. 86 redrawn in the form of horizontal bars such as were seen in Chapter I and Chapter II. The relative times for the various operations are shown much more clearly by the horizontal bars than by the curves used in Fig. 85 and Fig. 86. The time in seconds required for each operation is given by detailed dimension lines above each section in the horizontal bar, and the comparative total time of the two different men can also be grasped instantly. The total time in seconds for the whole series of operations is shown by an over-all dimension line above each of the bars, and the reader, if he wishes, may make an accurate comparison between operator No. 1 and operator No. 2 by using a numerical ratio. A chart of this kind can be very quickly made for ordinary office purposes if the horizontal bars are drawn on co-ordinate paper

CURVE PLOTTING

and the different areas made to stand out in contrast by the use of colored crayons. The actual differences between the two operators would show more clearly, operation by operation, if lines were used joining the ends of the components in the two bars in a manner similar to that seen in Fig. 32. The data of Fig. 85 do not lend themselves well to presentation in curve form. In Fig. 85 and in Fig. 86 the shape of the curves means nothing, since there is no numerical scale relating to the names of operations. Fig. 87 shows a much more satisfactory method for portraying the data.