Page:Graphic methods for presenting facts (1914).djvu/381

 27. Have all pencil lines which might show in the engraving been erased?

28. Is there any portion of the illustration which should be cropped off to save space?

29. Are the instructions for the final size of the plate so given that the engraver cannot make a mistake?

30. Is the chart in every way ready to mark "O.K"?

The English language has a grammar with hundreds of detailed rules concerning almost every possible construction. Though graphic presentations are used to a very large extent to-day there are at present no standard rules by which the person preparing a chart may know that he is following good practice. This is unfortunate because it permits every one making a chart to follow his own sweet will. Many charts are being put out to-day from which it would seem that the person making them had tried deliberately to get up some method as different as possible from any which had ever been used previously. Anyone of us would be thought of as a freak instead of as a genius, if he tried to invent his own constructions for the English language and to place words in some order never before seen, yet many persons are doing something akin to this when they attempt to present data by some new and outlandish method of charting. Below are given a few rules which may be of assistance toward getting graphic presentations more on a standard basis so that they may be instantly read. These rules are included here simply as suggestions, and they should be considered as only tentative until such time as definite rules have been agreed upon and sanctioned by authoritative bodies.

RULES FOR GRAPHIC PRESENTATION

1. Avoid using areas or volumes when representing quantities. Presentations read from only one dimension are the least likely to be misinterpreted.

2. The general arrangement of a chart should proceed from left to right.

3. Figures for the horizontal scale should always be placed at the bottom of a chart. If needed, a scale may be placed at the top also.

4. Figures for the vertical scale should always be placed at the left of a chart. If needed, a scale may be placed at the right also.

5. Whenever possible, include in the chart the numerical data from which the chart was made.