5 88 THE POPULAR SCIENCE MONTHLY. 



either flexed or kept straight. The thumb is simply extended back- 

 ward, and somewhat abducted from the fingers ; and a twitching of 

 the fingers is frequently observed. 



The energetic or powerful hand is the reverse of this, and is prob- 

 ably seen in life only under certain conditions of the mind, producing 

 what we call " mental states," or states giving energy and the feeling 

 of strength. 



The most natural position of the hand is that of rest, and here 

 analysis shows all the joints in flexion. The hand may be seen in per- 

 fect rest during sleep, or when the man is resting, engaged in quiet, 

 unexciting conversation. 



The antithesis of this is a hand in general extension or ortho-exten- 

 sion. The term ortho-extension is used to imjdy that the joint is so 

 far extended as to place both the bones constituting tbe joint in the 

 same straight line. If extension be full or complete, the bones form 

 an obtuse angle with each other. 



In the " ortho-extended hand," the axes of the metacarpal bones 

 (hand-bones) and of the digits are in the same plane with the bones of 

 the fore-arm, and the position is represented in which a strong man 

 naturally holds out his hand when requested to put it forward. A 

 healthy child, when it runs in its play or to meet a friend, commonly 

 holds out its arms, the hands assuming the " energetic position " ; and 

 this, as the result of observation, is, I think, characteristic of a healthy, 

 nerve-muscular condition ; healthful children in pictures by the best 

 masters are often thus represented. When a child is in a state of 

 convulsion it is well known that usually the hand is closed, with the 

 thumb turned in upon the palm, the fingers being flexed around it. 

 Such a position of the band in a child when ill is very indicative of a 

 state of the nervous system predisposed to convulsions. 



Equally characteristic with the passive positions of the hands are 

 the muscular movements of the fingers twitching, tremors, and rhyth- 

 mical movements. These conditions have been more fully studied 

 and described than the characteristic passive positions (postures), and 

 they have long been considered as visible muscular conditions express- 

 ive of the states of the nerve-centers. The varieties of finger-twitch- 

 ing may be described as 1. Flexor-extensor, the primary movement 

 being that of flexion, followed by a secondary extension movement. 

 This may be seen in a variety of cases, and in particular is seen in 

 what is called "picking the bedclothes" in the typhoid state preceding 

 fully developed coma. 2. Extensor-flexor, the primary movement being 

 that of extension, followed by a secondary flexor movement. This is 

 common in the slighter forms of chorea and in nervous children ; such 

 twitches usually constitute the subsultus tendinmn so indicative of 

 exhaustion in the course of typhoid fever. 3. Abductor - adductor 

 twitches, the movements consisting in lateral separations of the fin- 

 gers, followed by their being drawn together again. 



