CHAP. XIII. BLUSHING. 309 CHAPTER XIII. SELF-ATTENTION—SHAME—SHYNESS—MODESTY: BLUSHING. Nature of a blush—Inheritance—The parts of the body most affected—Blushing in the various races of man— Accompanying gestures—Confusion of mind—Causes of blushing—Self-attention, the fundamental element— Shyness—Shame, from broken moral laws and conven- tional rules—Modesty—Theory of blushing—Recapitu- lation. BLUSHING is the most peculiar and the most human of all expressions. Monkeys redden from passion, but it would require an overwhelming amount of evidence to make us believe that any animal could blush. The red- dening of the face from a blush is due to the relaxation of the muscular coats of the small arteries, by which the capillaries become filled with blood; and this de- pends on the proper vaso-motor centre being affected. No doubt if there be at the same time much mental agi- tation, the general circulation will be affected; but it is not due to the action of the heart that the network of minute vessels covering the face becomes under a sense of shame gorged with blood. We can cause laughing by tickling the skin, weeping or frowning by a blow, trembling from the fear of pain, and so forth; but we cannot cause a blush, as Dr. Burgess remarks,1 by 1 * The Physiology or Mechanism of Blushing/ 1839, p. 156. I shall have occasion often to quote this work in the present chapter.