CHANGE OF POSTURES. 143 



We will suppose that the right arm, as in Diana 

 (see Fig. 34), is holding a spear firmly; a strong 

 nerve-current is being sent to the muscles of the right 

 forearm, causing the hand to grasp the spear. In 

 order that this position of the hand may change, the 

 stimuli coming to the muscles of the limb .must 

 change ; they may be all reduced in strength, or their 

 relative strength may be altered. If the woman is 

 startled, she may drop her spear ; if she meet a 

 friend, she may purposely throw it away, and then 

 the hand is free to be acted upon again by its 

 nerve-mechanism, the action in the hand produced 

 by the central organ being thus directly expressed. 

 It is in a free and disengaged limb or part that we 

 best see direct expression. The hand of an ener- 

 getic speaker, if it is not engaged in leaning on the 

 table, or holding a paper, etc., will often express by 

 its movements the general mental state of the 

 speaker. The limb is moved by the strongest motor 

 stimuli that come to its muscles. We see, then,^that 

 in the case supposed, the strongest motor impulses 

 coming to the muscles of the limb when it is 

 disengaged, are in some way connected with the 

 mental condition of the subject. If, on commencing 

 to speak, the man hold his hat in his left hand, it is 

 probable that he will continue to hold it throughout 

 his speech. The motor currents to the left side are 

 continuing uninterruptedly, but it may be that (as 

 it is said) his emotion may be so strong, that the 

 current produced by emotion proceeding to his arm 

 will be stronger than the original current ; then he 

 will drop his hat and gesticulate with his arm. It 



