264 THE METAPHYSICS OF SENSATION 



If, while the sovereign lies on the hand, the 

 latter being kept quite steady, the fore-arm is 

 gradually and slowly raised; the tactile sensations, 

 with all their accompaniments, remain exactly as 

 they were. But, at the same time, something 

 new is introduced; namely, the sense of effort. 

 If I try to discover where this sense of effort 

 seems to be, I find myself somewhat perplexed at 

 first; but, if I hold the fore-arm in position long 

 enough, I become aware of an obscure sense of 

 fatigue, which is apparently seated either in the 

 muscles of the arm, or in the integument directly 

 over them. The fatigue seems to be related to 

 the sense of effort, in much the same way as the 

 pain which supervenes upon the original sense of 

 contact, when a pin is slowly pressed against the 

 skin, is related to touch. 



A little attention will show that this sense of 

 effort accompanies every muscular contraction by 

 which the limbs, or other parts of the body, are 

 moved. By its agency the fact of their movement 

 is known; while the direction of the motion is 

 given by the accompanying tactile sensations. 

 And, in consequence of the incessant association 

 of the muscular and the tactile sensations, they 

 become so fused together that they are often con- 

 founded under the same name. 



If freedom to move in all directions is the very 

 essence of that conception of space of three dimen- 

 sions which we obtain by the sense of touch; and 



