(12) Interest in the act and products of drawing.
(13) General intelligence.
These two analyses may serve as samples, since they include practically all the elements suggested by any other investigators. Jones has recently furnished us with additional evidence that memory of objects visually perceived and perception of perspective are probably important contributors to drawing ability. Among 264 school children in the seventh and eighth grades of the Evanston public schools, a correlation was found of .83 between visual memory and ability to draw. Perception of perspective and visual memory yielded a coefficient of .85.
As a result of administering more than twenty tests to 19 individuals gifted in drawing, Manuel concludes that, “Persons talented in drawing exhibit great individual differences in their psychophysical characteristics.” Nevertheless, tests devised to measure status in the traits listed in the analyses which have been made, would be expected to yield, finally, a psychograph of talent in each of the various kinds of drawing. Persons approximating these psychographs could then be identified as talented in drawing, and those deviating widely from them could be classified as deficient in ability to draw. The invention and standardization of such tests is a matter for further research. At present we have no means of gauging talent in drawing except by grading a finished product on a scale of drawings, like Thorndike’s “Scale for Measuring Achievement in Drawing.” Such a means does not always adequately separate talent from training.
The hope that psychographs of ability to draw may be platted in future does not mean that psychologists expect to find complete similarity among those talented in drawing. Individuality is as intrinsic in drawing as it is in handwriting. As a signature can be used for identification in the hands of experts, so a picture bears the mark of the particular psychophysical constitution that produced it. The ordinary reader of current fiction knows, by inspection, whether a given illustration has been made by May Wilson Preston or by Tony Sarg, without seeing the signature. The drawings of Clarence Day are inimitable.
IV. RELATIONS BETWEEN APTITUDE IN DRAWING AND GENERAL INTELLIGENCE
As long ago as 1903, Fischlovitz studied 350 high school freshmen, to obtain the correlation between ability to draw and ability in other high school studies. Correlations were computed between grades in drawing and in other subjects. The conclusion was that, “Ability in drawing is correlated to a greater degree with some of the subjects than with others, but in no case is the correlation very strong, and that ability in drawing is more of a special ability.”
Some years later, Elderton obtained a correlation of .416 between grades in drawing and grades in classics, for one class, and of −.313 between the grades in the same studies, in another class. The subjects were here 19 boys in each of two classes in an English public school. Ivanof found among Swiss children a tendency for the able in drawing to include somewhat more good all-round pupils than were included among the pupils at large, and an opposite tendency among those poor in drawing. The figures show, however, many pupils strong in general work listed among those poor in drawing. Ayer obtained a correlation of .66 between grades in drawing and other subjects, for 141 normal school students.
As Ayer points out, these methods are very crude as means of determining to what extent drawing is a special ability. In the first place, since drawing is used as a form of recitation in various school subjects, we are obtaining to some extent a self-correlation in subjects like science and geography. In the second place, grades in drawing do not specify what kind of drawing is graded. In the case of Ayer’s normal school students, special inquiry showed that the grades in drawing were computed from heterogeneous factors, including (a) ability in representative drawing, (b) ability in designing, (c) ability in artistic discrimination, (d) ability with color, washes, shading, etc., (e) attendance, (f) discipline, (g) vocational interest. School marks do not, therefore, isolate ability in any one kind of drawing, from a medley of other relevant and irrelevant factors, the mark being bestowed upon the total composite of factors.
Much more reliable as a method of research is the method of tests. In Simpson’s data, already quoted, it is seen that drawing lengths shows very slight coherence with other abilities. Other similar fragmentary suggestive facts may be found, scattered through the literature. In 1916 Ayer undertook a well-planned investigation to determine how two kinds of drawing, (1) representative drawing and (2) analytical drawing, are related to (a) ability in verbal description and (b) achievement in school subjects on the whole.