It is no wonder, therefore, that all his life long man shows a peculiar interest in movement, and acquires the capacity to detect its intimations very early in life. Indeed, this capacity is one of the first to be developed, and depends, apart from skin stimuli and the so-called after images which reveal objective movement to the eye at rest, principally on the ability to follow the moving object with the glance. Practice is necessary for the mastery of this capacity. The eyes accompany, in addition to the regular objective motion, a constantly renewed backward movement as well, by means of which we again grasp the escaping object, an effort requiring the simultaneous exercise of volition and attention. “This process requiring continuous and constantly renewed attention,” says L. W. Stern, “this lying in wait that the object may not give us the slip (for any laxity would at once be avenged by an increased difficulty in fixing the object), bears witness to a condition and teaches us that the object with which we are carrying on this game of ‘catcher’ is in motion.”[144] This explains why little children so easily lose sight of a moving object which they wish to follow with the eye.
Here again we find that playful experimentation is essential, and, according to Raehlmann, it commonly appears toward the end of the fifth week, rarely earlier.[145] That Preyer’s boy on the twenty-third day followed with his eyes a slowly moving light was probably an instance of forced development, as a result of much experimenting. On the twenty-ninth day the same child crowed aloud at the sight of a swaying tassel. On the sixty-second day he gazed at a swinging lamp with constant manifestations of delight for nearly half an hour, but his eyes did not follow the swing of the pendulum; they moved, it is true, now left, now right, but not in time with the lamp. “On the one hundred and first day a pendulum making forty complete swings in a minute was for the first time followed with mechanical exactness by his glance.”[146] As his capacity for following the movement increased, the greater his interest in it became. A dog racing away or leaping about the child, the fast horse, the hopping toad, the crawling worm or gliding snake, running water, leaping flame, a rolling wagon, and, more than all, the fast-rushing train, with its cloud of steam—all these excite a really passionate sympathy. The smoke of a cigar, too, gives great satisfaction, and if a father knows how to make the beautiful blue rings he must at once renounce his peaceful contemplative enjoyment of his own play, for the youngster will demand a very different tempo in the repetition than is agreeable to him. In enumerating instances of animal motion I omitted one because it deserves more extended notice—namely, the flight of insects, in which children take such lively interest. The common illusion that an insect which has been caught can be induced to fly away by the recital of a form of words is highly interesting, in itself considered as well as in view of its probable origin. May not such poetic formulæ be traceable to a religious or at least superstitious origin? The commonest of these rhymes are those addressed to the ladybird (Coccinella septempunctata) and the June bug. Rochholz has made a collection of the names of the former, and found that in India it was sacred to the god Indra, and among the old Germans to Frega. I give two German forms of the verse:
“Muttergotteshühle, Mückenstühle,
Fliege auf, fliege auf! Wohl über die Bussenberg,
Dass es besser Wetter wird.”
“Marienkäferchen, wann wird Sonne sein?
Morgen oder heut?
Flieg weg in den Himmel!”
An English one is:
“Ladybird, ladybird,