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 *fore given greater width than any other State in proportion to the greater size of its electoral vote. The horizontal division has been made according to the percentage number of votes for each of the main political parties. Two different elections are shown by using solid lines and dotted lines. The chart proves that the Democratic vote of 1913 was essentially the same as the Democratic vote in 1908, and that a Democrat was elected President in 1912 largely because there were three candidates in 1912 and only two in 1908. This is an admirable piece of presentation even though the lettering and drafting are not quite as good as they might have been if more care had been used, though probably allowance must be made for the limitations of paper and presswork in daily newspaper printing.

Massachusetts Institute of Technology—Vehicle Research

Fig. 9. The Factors Entering into the Annual Cost of Motor Trucking Service

The scheme of this convenient form of tabulation is somewhat similar to that of Fig. 5. Here, however, the components are only named without denoting their relative size or importance

When studying a number of varied components, and the relations of each to every other one, a chart like Fig. 9 is frequently of great assistance. This chart shows that certain components are affected by features which may not affect other components. We have here the total cost of motor trucking, studied according to the components of the cost and also according to the conditions which produce those component costs. We may consider either the service conditions or the cost components. We have 100 per cent in the horizontal direction and 100 per cent also in the vertical direction. The total of the components in either direction is 100 per cent, but the actual size of each is not given because the size is not known or because it may vary from time to time.