100 



nied by pain, or, in fact, any sensation whatever. A man, 

 named John Colburn, from an injury to the lower part of the 

 brain where it joins the spinal cord, was deprived of all sensa- 

 tion in his body ; but possessed all Ins faculties entire, and 

 the power of sense and motion in the head and face. He lived 

 in this condition for some months, and eventually recovered. 

 He formed, at one time, a most remarkable illustration of the 

 existence of what is called, in the technical language of physi- 

 ologists, the reflex power — (a power, that is, by which certain 

 motions, called instinctive, follow certain impressions. It is by 

 this faculty that we are enabled to stand without looking at our 

 legs; to hold substances in our hands when we are not conscious 

 of their presence ; and it is this which leads a sleeping cliild to 

 grasp a finger placed on his palm, or to move away when tickled.) 

 If the hand was pinched, the arm of the patient instantly flung 

 itself away. If the palm was lightly touched by a feather, the 

 whole limb would become convulsed, and the other arm would 

 begin to quiver. If the toes were pinched, the leg was forcibly 

 drawn away, and if the sole of the foot was tickled, the man 

 would be almost thrown out of bed by the violent convulsive 

 movements of the legs. A hot plate to this sensitive spot made 

 lmn literally shake the bed with the energy of Ins movements, 

 and the action of micturition made every limb quiver. As he 

 recovered, he was taken up and supported in walking; but 

 though^ he did not fall down, he could make no progression, be- 

 cause, whenever one foot touched the ground it was darted up 

 again, and the body turned half round on the other leg, as on a 

 pivot. The cause of this was not at first detected ; but on his 

 being experimented on in bed, this same result was found to 

 take place whenever a corn on his bttle toe was touched. So 

 marked, in this case, was the connexion between cause and 

 effect ; so decided the shrinking from what would, in us, pro- 

 duce pain, that few could have stood by without upbraiding the 

 experimenters with cruelty. Look, such persons would have 

 said, how he winces when you prick him ; how he starts when 



