See Volume M, Verso 40, Manuscripts of the Institute of France. He used horizontal distances to express time and vertical distances to show the space covered by falling balls when two were dropped together or one following the other. Leonardo, however, left no group to carry on his engineering works, which were little understood by his immediate contemporaries and successors. The American Statistical Association, formed in 1839, now celebrating its one hundredth anniversary, is the earliest specialized scientific organization in this country. The American Philosophical Society, organized by Benjamin Franklin in Philadelphia, was, of course, earlier but its activities cover such a wide field as to put it in a different class. The American Society of Civil Engineers founded in 1876, was followed by the American Society of Mechanical Engineers in 1880 and then by numerous other engineering and scientific societies. The presentation of their papers in edited transactions has resulted in rapid advance in varied chart techniques.

In spite of all that Playfair pointed out a century and a half ago, and the interest shown by a few college instructors during recent years, there is still insignificant use of graphic presentation

Early Work on Books Was Done Monasteries

GRAPHIC PRESENTATION

methods in the field of education. Educators themselves do relatively little to analyze the methods for transmitting facts and ideas.

At present most educators are graphically illiterate. An educator, or person with a message to give is referred to as : lecturer, speaker, orator, preacher, narrator, reciter, etc. These words generally imply the conveyance of a message through the ear without reference to the eye. Until the cinema was equipped with sound there was a move to use the word "optience" instead of "audience." Although the moving picture now combines perception through both the eye and the ear, the messages generally conveyed today by the motion picture are descriptive rather than quantitative.