CHAP. II—GENERAL PRINCIPLES OF EXPRESSION.—_continued_. The Principle of Antithesis—Instances in the dog and cat—Origin of the principle—Conventional signs—The principle of antithesis has not arisen from opposite actions being consciously performed under opposite impulses CHAP. III—GENERAL PRINCIPLES OF EXPRESSION.—_concluded_. The principle of the direct action of the excited nervous system on the body, independently of the will and in part of habit—Change of colour in the hair—Trembling of the muscles—Modified secretions—Perspiration—Expression of extreme pain—Of rage, great joy, and terror—Contrast between the emotions which cause and do not cause expressive movements—Exciting and depressing states of the mind—Summary CHAP. IV—MEANS OF EXPRESSION. IN ANIMALS. The emission of sounds—Vocal sounds—Sounds otherwise produced—Erection of the dermal appendages, hairs, feathers, &c., under the emotions of anger and terror—The drawing back of the ears as a preparation for fighting, and as an expression of anger—Erection of the ears and raising the head, a sign of attention CHAP. V.—SPECIAL EXPRESSIONS OF ANIMALS. The Dog, various expressive movements of—Cats—Horses—Ruminants—Monkeys, their expression of joy and affection—Of pain—Anger Astonishment and Terror CHAP. VI.—SPECIAL EXPRESSIONS OF MAN: SUFFERING AND WEEPING. The screaming and weeping of infants—Form of features—Age at which weeping commences—The effects of habitual restraint on weeping—Sobbing—Cause of the contraction of the muscles round the eyes during screaming—Cause of the secretion of tears CHAP. VII.—LOW SPIRITS, ANXIETY, GRIEF, DEJECTION, DESPAIR. General effect of grief on the system—Obliquity of the eyebrows under suffering—On the cause of the obliquity of the eyebrows—On the depression of the corners of the mouth CHAP. VIII.—JOY, HIGH SPIRITS, LOVE, TENDER FEELINGS, DEVOTION. Laughter primarily the expression of joy—Ludicrous ideas—Movements of the features during laughter—Nature of the sound produced—The secretion of tears during loud laughter—Gradation from loud laughter to gentle smiling—High spirits—The expression of love—Tender feelings—Devotion CHAP. IX.—REFLECTION—MEDITATION—ILL—TEMPER—SULKINESS DETERMINATION. The act of frowning—Reflection with an effort or with the perception of something difficult or disagreeable—Abstracted meditation—Ill-temper—Moroseness—Obstinacy—Sulkiness and pouting—Decision or determination—The firm closure of the mouth CHAP. X.—HATRED AND ANGER. Hatred—Rage, effects of on the system—Uncovering of the teeth—Rage in the insane—Anger and indignation—As expressed by the various races of man—Sneering and defiance—The uncovering of the canine teeth on one side of the face