72 Facial Expression. 



by applying a slight electric shock to each muscle individually, 

 caused it to give up the secret of what action it was for which 

 it had been specially adapted. He found that the action of 

 any single muscle alone would not produce a characteristic 

 expression of human feeling, but that, as in music, so here the 

 overtones of expression must be added to give full sig- 

 nificance to the fundamental note of feeling first hit upon. 

 His researches shew that most of these characteristic expressions 

 involve movements about the mouth combined with correlated 

 movements of the nostrils and the eyes. This corresponds 

 accurately with what Sir Charles Bell pointed out early in the 

 century, that the facial muscles are divisible into three natural 

 groups, each group in turn consisting of two antagonistic series 

 of muscles acting respectively towards, and away from, the 

 apertures of the mouth, the nostril, and the eye. He further 

 shewed that a certain class of mental activities is associated 

 with the action of the retracting muscles, and a contrary class 

 with that of the contracting series ; while contending impulses 

 opposite in their character, often produce those uncertain 

 tremors of balanced activity so characteristic of an undecided 

 frame of mind. Speaking generally, the retracting muscles are 

 associated with amiable impulses, the contracting group with 

 the opposite. But it is to be noticed that in hardly any case 

 can one glean the full significance of an expression from the 

 action of one feature alone : hence it is by no means easy to 

 ascribe a leading part in expression to any one of them. 

 Practically, however, I think it will be found that the mouth 

 gives as it were the key-note of the expression, whether grave 

 or gay : and that one must look to the subtler significance of 

 the eye to determine precisely the type of gaiety or gloom 

 present in each case. It is said that some people smile with 

 their eyes only ; but does not such an expression convey rather 

 an anticipatory conception of what may be, than the actual 

 sense of organic satisfaction in the accomplished fact, where the 

 mouth smiles too ? Of the converse, I need hardly speak ; — 

 a smiling mouth, with hard cold unsmiling eyes, is not an 

 attractive expression, as a true smile should always be. Thus 



