Page:Popular Science Monthly Volume 85.djvu/286

282 is different from understanding them. Merely to go into the fields is not to study botany, and unless we carry that definite aim with us the stroll is much more likely to add to our dumb enjoyment than to extend our knowledge. The eye may be filled while the mind is left untouched; for it is just when sense is thus completely satisfied that reflection is most likely to lie unstirred.

The vogue of illustration, as an adjunct of public lecturing, marks such a change of habitual attitude. We go to the lecture, as to the theater, to be entertained, not to be instructed; and are so absorbed in looking that we cease to think. A swift succession of vivid impressions, resplendent in color or palpitating with motion, passes before the gaze. There is as little leisure for reflection as directive stimulation to thought. The senses are stimulated and at last jaded, as picture succeeds picture and topic replaces topic; until, breathless with the dizzying rush of scenes, we are at last tossed back, momentarily bewildered, into normal relations with the world about us.

Under such conditions the verbal commentary of the lecturer becomes a matter of secondary importance, and we accept a mediocrity of merit, or even a literal incoherence, which would never have been tolerated under the more exacting conditions of the lyceum. Indeed, if the pictures be only chosen skilfully enough the text may be rendered wholly negligible, as the kinetoscopic theater indicates by its elimination. In a word, the speaker has been replaced by the picture-machine, and a corresponding change in our conceptions of merit has accompanied the substitution. We require better and ever better pictures and promote a race for mechanical perfection. We stimulate the ingenuity of inventors to devise fresh marvels of reproduction; color is added to form, and motion to color; but still we demand more. The world is ransacked for its treasures of picturesqueness or beauty, and men's brains racked to conceive new dramas and burlesques of action. As a result these pictorial and esthetic demands finally supersede the lecturer's original function of interpretation.

This trend has perhaps been most striking where it has been least justifiable, in connection with the presentation of scientific materials. The change is at least suggested in the subordination of theoretical to experimental and demonstration methods in teaching. The aim of scientific instruction is to put the mind in possession of a system of explanatory concepts. These are necessarily abstract and can not be set forth in the form of concrete examples. There is therefore a danger that attention, detained by its purely picturesque aspects, may recall the demonstration merely as an impressive spectacle, and thus lose sight of the principles which it illustrates. The use of demonstration methods in the class-room, however, presents less subversion of aim than that of platform illustration. The lantern-slide has won a secure place in the