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effect of a species of paralysis, in which the sense of muscular motion 

 was lost, whilst the power of action remained. 



Referring to the experiments of Weber and others, bj pricking the 

 skin, he stated, that on pricking certain parts of the body with two 

 sharp points at the same moment, there was a sensation of one point 

 only, whilst, on other parts, the sensation of the two points was dis- 

 tinct. Those experimenters drew the conclusion that this capacity of 

 distinguishing the two points resulted from the greater concourse of 

 nervous filaments. He stated, on the contrary, that the capacity 

 of distinguishing the two points, or, in fact, of distinguishing the 

 form of bodies, did not result from the mere sensibility of the part ; 

 for example, that the back of the hand was painfully pricked, and 

 yet was not capable of distinguishing the two points from the one. 

 He contended, on the contrary, that the capacity resulted from the 

 junction of sensibility and motion. It was limited to the hand, the 

 tongue, and the lip. 



Pricking the cheek with two points gave no distinct sensation, but 

 on approaching the lower lip the points become distinct. And not 

 only the sensibility to form, but to weight also, results from the 

 combination of muscular motion. Hence the sovereign and the 

 shilling may be distinguished by their weight on being placed on 

 the lip or tongue, though not by any less moveable part. 



The author proceeded to consider the motions of the eye, arguing, 

 that to the full exercise of the organ in vision the action of the 

 recti muscles of the eye was necessary, and that a sense of their 

 action was combined with the inipression on the retina. 



After some instances drawn from the musci volitantes, and the 

 experiments of Dr Vrells, he stated, that when the impression was 

 permanent on the spot of the retina, the eye being closed, the per- 

 ception of place was received from the sense of the action of the 

 recti muscles. But if the ball of the eye was moved by the point 

 of the finger, or by the oblique muscles, there was no apparent 

 change in the place of the image. On this subject, he referred to 

 the case of the nystagmus hulbi, in which there was an incessant 

 motion of the eyeball, whilst the person saw distinctly, and could 

 perform most minute works with the needle or the pencil. 



The fact on which the author placed the greatest stress was the 

 eflFect of cutting one of the recti muscles. He referred to a late 



