58 THE HUMAN BODY. 



will, it can neither prevent them nor arrest their develop- 

 ment. It is the same with the chattering of the teeth, with 

 shivering and winking of the eyelids on contact with the air, 

 with the tears, or only when a foreign body menaces the eye. 

 In this last case, although the muscular contraction is in- 

 stantaneous and seems to be involuntary, it is evidently pre- 

 ceded by a sensation which the eye has transmitted to the 

 brain. This may even be considered as voluntary, since if 

 the attention is excited, the will can oppose the instinctive 

 movement. 



Other movements take place in the organism of which we 

 have more or less perception; when a carriage threatens to 

 overset, for example, we throw ourselves to the side opposite 

 the inclination ; or when suddenly coming on the edge of a 

 precipice the body stiffens or is thrown backward; and when 

 a player at ball or billiards inclines or turns in the same direc- 

 tion in which he wishes to direct his ball. Analogous 

 phenomena are caused by a sort of attraction or instinctive 

 imitation. When, for example, the eyes follow the move- 

 ment of a great waterfall into a gulf, the body very soon fol- 

 lows the oscillations, though we do not perceive them until 

 the motion becomes so great as to threaten to drag us into 

 the abyss. We are indebted to M. Chevreul for the obser- 

 vation and explanation of effects of this nature, of which 

 charlatanism avails itself in table-turning. If the elbow be 

 placed upon a table, and a pendulum formed of a string and 

 a ring be held in the hand, and we fix the eyes on the ring, 

 we shall soon see it begin to oscillate, although the arm ap- 

 parently remains immovable; the oscillations may keep the 

 same direction, or change according to the mental desire, 

 and this without any bad faith or a consenting movement on 

 the part of the person holding the pendulum. But if we 

 place a support under the hand near the end of the fingers, 

 or a bandage over the eyes of the experimenter, the oscilla- 

 tions cease. They were caused by an almost imperceptible 

 and involuntary movement of the fore-arm and hand, under 

 the influence of the eyes looking at the ring and the direc- 

 tion that it takes. And again it is a similar movement or 

 series of movements which gives the impulse to the turning 



