Each of these main-group bars is crosshatched to show the conjugal condition within the group. The combined length of the four bottom bars is equal to the length of the total-population bar shown at the top. These same data could have been presented by the method shown in Fig. 5. It will be noted, however, that in Fig. 6 all the figures have been included, and are available for reference purposes without detracting from the utility of the chart itself. The lettering was done by hand and shows the possibilities for neatness resulting from hand work when a skilled draftsman is employed. In many ways the method of Fig. 5 is preferable, but it is probably true that Fig. 6 would be more readily understood by the average untrained reader.

Where there are a large number of items to be compared and the components of each item are given, the method of Fig. 7 is a very convenient one. The Census Atlas for the 1900 Census contained manjr pages of charts of this type for its comparisons of different States. By placing bars for all the States on one page, the total for the country is shown as 100 per cent in the vertical direction. No vertical scale

I I I I i=f Scale fo inch equals 5 perceni

United Slates Statistical Atlas for the Census of 1900

Fig. 5. Elements of the Population of the United States in 1900

Here the components of the total population are shown in their relative sizes on the vertical scale. Each component is also divided into different subdivisions whose percentage size may be read from the horizontal scale. This is an admirable method of presentation if components must be subdivided