your eyes to the black dot on the right, and look at that a few seconds; then shift back again to the dot on Fig. 239 and look at that a half minute; then again to the dot on the right for a few seconds, [1] and after repeating these movements three or four times, finally look steadily at the dot on the right, and you will see a beautiful tint of the complement of red, and also a tint of the complement of sea-green, just the size and shape of Fig. 239. The reader will observe that the red tint is below the sea-green tint, which is just the reverse of the position of the colors in Fig. 239. If the two tints produced by this experiment are similar to the actual tints of the colors which call them into view, then the colors shown in Fig. 239 are complementary. If this experiment be tried with Fig. 242, the reader will find that the complement of green is a reddish purple.
Now cover all of the figures except 239 and 241. Repeat the experiment just described, shifting the vision alternately between the black dot on Fig. 239 and the white dot on Fig. 241, finally allowing the eyes to rest on the white dot. In this case you will see deep shades of the complements of red and sea-green instead of tints as in the first experiment. Try this experiment with Fig. 242 and you will see deep shades of the complements of green and reddish purple.
We will now show the effect of looking at a color for several minutes, then suddenly looking upon its complement for a few
seconds. The result will be that the color last looked at will appear almost as brilliant as a prismatic color. First cover all of the figures except 239 and 240. Then look very intently at the black dot on Fig. 239; after the colors have become somewhat dull to the eye, suddenly shift the vision to the dot on Fig. 240. The result is most pleasing, as the colors in the latter figure seem to be increased in
- ↑ The movements described are repeated for the purpose of building up, or making stronger the complementary tint which is called into view.
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