OCR Text |
Show CIIAP •• il t. CltA:PfER Ill. GENE~AL PRINOIPLES OF ExPRESSION-concluded. ~rho principle of the uit·ect action or the excitec~ nervous systm~l on the body, inllcpcnuently or the will an~ lll ~art of habtt -- cl utnfrc o (. co 1o ur 1' 11 lIJ} te h( air- rfremblmg • ot the DlUScles•- Mo liflell :;ecretion~- Perspiration- Express LOn of extreme ~am Of . . , t · y ancl terror- Contra::;t beL ween the emotiOns - mere, gte£1. JO ' E . . which c~use and ·do not cause expressive movmnents - ~ xctlmg ancl depressing otates of Lhe mind -Hummary. vVE now come to our third Principle, na~e1y, that c~rtain a ·tions, which we recognise as expressive of certain states of the mind, arc the direct result of t!1e constitution of the nervous system, and have been fro1n the. first independent of the will, and, to a larg~ extent, ot habit. When the sensorinn1 is strongly exc1ted nerveforce is generated in excess, ancl is trans1nitted in certain directions, dependent on the connection o~ the nervecells, and, as far as the n1uscnlar systen1 IR concerned, on the nature of the n1ovements which have been habitually practised. Or the supply of nerve-force may, as it appears, be interrupted. Of course every ~ov?ment which we make is deter1ninecl by the constitution of the nervous system; but actions performed in obedience to the will, or through habit, or through the principle of antithesis, are here as far as possible excluded. 0ur present subject is very obscure, but, fro1n its importance, must be discussed at some little length; and it is always advisable to perceive clearly our ignorance. . The most str1 king case, though a rare and abnonnal CrrAP. 1 rt. 61 one, which can be adcln ·eel of the direct inflnen e of th nervous system, wh~n strongly affect cl, on th b ely, is the loss of colour In th hair, which has occa ionally been o?se~·ved after extr tne terr r or grief. One authentic Instance has b en recorrled, in tho cas of a man brought out for execution in India, jn whi ·h the change of colour was so rapid that it was perc ptibl to the eye.1 Another good case is that of the tren1blino- of th 1nnscles, which is co_mmon to 1nan and to ~any, or most, of the lower animals. rrt·embling is of no service often of mnch disservice, and cannot have been at firs~ acquired through the will, and then renclerefl habitual in ~1ssociation '~ith any emotion. I am assured by an eminent authonty that yonng children do not tre1nble, but go into convulsions under the ciecumstances which would induce excessive trembling in adults. TremblinO' is excited in different individuals in very different d:grees, and by the 1nost diversified canses,-by cold to the surface, before fever-fits, although the temperature of the body is then above the normal standard ; in blood-poisoning, delirium tremens, and other diseases ; by general f~Lihue of power in old age; by exhaustion after excessive fatigue ; locally from severe injuries; such as burns ; and, jn an especial manner, by thn ~assage of a catheter. Of all emotions, fear notoriously 1s the n1ost apt to induce trembling ; but so do occa~ sionally great anger and joy. I ren1ember once seeing a b~y who had just shot his first snipe on the wing, and his hands tre1nbled to such a degree from delight, that he could not for some ti1ne reload his gun; and I have l Soo tho inter ~ting cascl:l colloctct l by 1\i. u. Pone hot ln tho ' n 'VUe de!:i Doux 1\I ndos,' January 1, 1872, p. 70. Au ins Lance was ab<1 brought some years ago before the Brlti~;h Association at Bolfa.st. ~, ~ |