A study of talent in drawing
An educational psychology monograph by Herschel T. Manuel, published in Bloomington, Illinois, in 1919, reporting tests of drawing ability among schoolchildren for researchers in mental measurement. The plates are profile charts on ruled grids: several score lines in solid, dashed, and dotted strokes zigzagging across a numbered scale, usable as raw line-pattern material, chart furniture, and examples of early graph notation.
