REPORT ON ANIMAL MAGNETISM. 153 



for example, that some people are absolutely blind to cer- 

 tain colours, as red, and enjoy perfect vision relatively to 

 yellow, to green, and to blue. If the Newtonian theory 

 of emission be true, we must irrevocably admit that a ray 

 ceases to be light as soon as we diminish its velocity by 

 one ten thousandth part. Thence flow those natural con- 

 jectures, which are well worthy of experimental exam- 

 ination : all men do not see by the same rays ; decided 

 differences may exist in this respect in the same individ- 

 ual during various nervous states ; it is possible that the 

 calorific rays, the dark rays of one person, may be the 

 luminous rays of another person, and reciprocally ; the 

 calorific rays traverse some substances freely, which are 

 therefore called diathermal, these substances, thus far, 

 had been called opaque, because they transmit no ray 

 commonly called luminous ; now the words opaque and 

 diathermal have no absolute meaning. The diathermals 

 allow those rays to pass through which constitute the light 

 of one man ; and they stop those which constitute the 

 light of another man. Perhaps in this way the key of 

 many phenomena might be found, that till now have re- 

 mained without any plausible explanation. 



Nothing, in the marvels of somnambulism, raised more 

 doubts than an oft-repeated assertion, relative to the 

 power which certain persons are said to possess in a 

 state of crisis, of deciphering a letter at a distance with 

 the foot, the nape of the neck, or the stomach. The word 

 impossible in this instance seemed quite legitimate. Still, 

 I do not doubt but some rigid minds would withhold it 

 after having reflected on the ingenious experiments by 

 which Moser produces, also at a distance, very distinct 

 images of all sorts of objects, on all sorts of bodies, and in 

 the most complete darkness. 



