226 



THE HUMAN BODY. 



the object which touches us, but that part of the tegument 

 where the contact takes place and the impressions which 

 it receives. The idea of external objects given by touch 

 then is, when completely analyzed, the possibility of distin- 

 guishing the different parts of the body as occupying a 

 different place in space. The result is, that if the parts of 

 our bodies are momentarily in an abnormal condition, we 

 receive, notwithstanding, the sensation in the relative order 

 that the regions from which these sensations emanate pre- 

 serve in a normal condition. If, for example, we cause .a 

 ball to revolve between two fingers of the same hand, we 

 have the sensation of a single body touching these two 

 fingers; but if we cross the fingers and place the ball between 



Fig- 43- 



their extremities, the sensation is that of two balls, each one 

 rolling in contact with one of the fingers. 



The sensations of touch are somewhat persistent, especially 

 when the tactile impression is joined to that of general sensi- 

 bility. Thus when we have carried a burden on the shoulder, 

 or when any part of the body has been subjected to great 

 and prolonged pressure, we still perceive the sensation some- 

 time after the weight is removed and the pressure has ceased, 

 but in such cases the tissues subjacent to the skin take part 

 in the sensation as well as the skin itself. 



The organ of touch may also be the seat of impressions 

 which are subjective, or which arise from internal causes, 

 physical or moral. The sight of a striking spectacle or the 

 emotion caused by a narrative produces in soire persons a 



