each other. The mucous surfaces share in this irritability of the
skin. The kiss is not only an expression of feeling; it is a
means of provoking it. Cataglottism is by no means confined to
pigeons. The tonic value of cutaneous stimulation is indeed a
commonly accepted idea. Wrestlers rub their hands or limbs, and
the hand-shake also is not without its physiological basis.

"Cutaneous excitations may cause painful sensations to cease. Many
massage practices which favor work act chiefly as sensorial
stimulants; on this account many nervous persons cannot abandon
them, and the Greeks and Romans found in massage not only health,
but pleasure. Lauder Brunton regards many common manoeuvres, like
scratching the head and pulling the mustache, as methods of
dilating the bloodvessels of the brain by stimulating the facial
nerve. The motor reactions of cutaneous excitations favor this
hypothesis." (Féré, _Travail et Plaisir_, Chapter XV, "Influence
des Excitations du Toucher sur le Travail.")

The main characteristics of the primitive sense of touch are its wide
diffusion over the whole body and the massive vagueness and imprecision of
the messages it sends to the brain. This is the reason, why it is, of all
the senses, the least intellectual and the least æsthetic; it is also the
reason why it is, of all the senses, the most-profoundly emotional.
"Touch," wrote Bain in his _Emotions and Will_, "is both the alpha and the
omega of affection," and he insisted on the special significance in this
connection of "tenderness"--a characteristic emotional quality of
affection which is directly founded on sensations of touch. If tenderness
is the alpha of affection, even between the sexes, its omega is to be
found in the sexual embrace, which may be said to be a method of
obtaining, through a specialized organization of the skin, the most