Fig. 52 was shown in conjunction with Fig. 51 with the idea of pointing out that the number of students in the University of Cincinnati had increased just as (according to Fig. 51) the number of firms co-operating in the engineering work of the University had

increased in the same time.

The bars in Fig. 51 and Fig. 52 are placed vertically, each bar representing a year. This vertical arrangement of bars permits reading the chart as if a curve had been made by drawing a line through the tops of all the bars. Curves are the common language of engineers and statisticians. In order that the bars may be read as curves, it is desir-

THE NUMBER OF FIRMS : CO-OPESATIMG WITH THE

ENGINEERING COLLEGE

OF THE

UNIVERSITY or CINCIHNATI

HAS INCREASED 289 y.

mm llll

American Reaiew of Reviews

Big. 51. The Increasing Number of Business Firms Co-operating with the Engineering College of the University of Cinciimati

^\'hen the bars represent years or other divisions of time, a vertical arrangement of the bars is usually more desirable than the horizontal arrangement seen in Fig. 44. With the vertical arrangement a line may be imagined joining the tops of the bars so as to give a "curve".

Note, in this illustration of a wall chart, the popular touch given by the pictures of manufacturing plants with smoke-stacks of the same height as the first and the last vertical bars

able to have the bars placed in a vertical position, if they represent divisions of time, rather than entirely distinct subjects such as the separate cities compared as to the value of their output of manufactured products, in the chart reproduced in Fig. 21. Lettering like that shown in Fig. 51 or Fig. 52 is conveniently made by using the gummed black-paper letters and figures which can be obtained in many good stationery stores.