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 an unfortunate one which should not be copied. Note that in Fig. 46 the figures have been arranged in groups of four with a blank space to assist the eye in reading across the page. In general, it is customary to have such figures not in groups of four but in groups of five, the groups including years ending in 1 to 5 inclusive and 6 to 10 inclusive.

A rapid reader seeing Fig. 47 is likely to get a much exaggerated idea of the increase in the American exports of automobiles. The arrangement of the three horizontal bars for the three years is such that the reader is justified in assuming that the years are consecutive. He is not likely to notice that the upper bar represents the year 1906 and that four years are omitted between 1906 and the consecutive years 1911 and 1912. Since there is nothing to indicate that years have been left out after 1906, the reader seeing the figure 1912 is apt to assume that the two earlier years are 1911 and 1910.

A MARVEL OF EXPORT TRADE

SHOWING THE AMAZING INCREASE IN OUR EXPORTS OF MOTOR CARS, AND THE STEADY DECREASE IN OUR IMPORTS, IN THE LAST SEVEN YEARS

World's Work

Fig. 47. This Illustration was Originally Printed with Fig. 45 on the Same Page of a Magazine, yet in Fig. 45 the Earliest Year was Shown at the Bottom While Here the Earliest Year is Properly Shown at the Top

There is, however, danger, in this illustration, that the reader may assume that the three bars represent consecutive years without noticing the jump from 1906 to 1911. Compare Fig. 48

Fig. 48. The Contrast of American Exports and Imports of Automobiles

The data of Fig. 47 have here been redrawn. The values have been shown at the left of the bars, where they give the neatest and most convenient arrangement. Note that the bar for 1906 is somewhat separated from the bar for 1911, so as to indicate to the reader that the three bars do not represent consecutive years

Fig. 48 is a redrawing of Fig. 47 with a change in scale to indicate to the reader that the earlier year shown for comparison must not be read as one of three consecutive years. Though the space left between the bars for 1906 and 1911 would not be sufficient for the four omitted years, if the whole chart were drawn to scale, the space is nevertheless large