B UFFON FULLER QUOTATIONS. 131 



of perception. In the head there are pure sensations 

 and nothing else, or rather, there are but the repre- 

 sentations of sensations stripped of the character of 

 perception ; that is to say, we can remember and call to 

 mind whether such and such a sensation was pleasant 

 to us or otherwise, and if this operation, which goes 

 on in the head, is followed by a vivid perception, then 

 the impression made is perceived in the interior of 

 the body, and always in the region of the diaphragm. 

 Hence, in the fcetus where this membrane is without use, 

 there is no perception, or so little that nothing comes of 

 it, the movements of the foetus, such as they are, being 

 rather mechanical than dependent on sensation and will. 

 " Whatever the matter may be which serves as the 

 vehicle of perception, and produces muscular movement, 

 it is certain that it is propagated through the nerves, 

 and that it communicates itself instantaneously from 

 one extremity of the system to the other. In whatever 

 manner this operation is conducted, whether by the 

 vibrations, as it were, of elastic cords or by a subtle 

 fire, or by a matter resembling electricity, which not 

 only resides in animal as in all other bodies, but is 

 being continually renewed in them by the movements 

 of the heart and lungs, by the friction of the blood 

 within the arteries, and also by the action of exterior 

 causes upon our organs of sense in whatever manner, 

 I say, the operation is conducted, it is nevertheless 

 certain that the nerves and membranes are the only 

 parts in an animal body that can feel. The blood, 

 lymphs, and all other fluids, the fats, bone, flesh, and all 

 other solids, are of themselves void of sensation. And 



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