Hold both hands in water which causes the thermometer to rise to ninety degrees, and when the liquid has become still, you will be insensible to the heat, and that the hand is touching anybody. Then remove one hand to water that causes the thermometer to rise to two hundred degrees, and the other in water at thirty-two degrees.

After holding the hands thus for some time remove them, and again immerse them in the water at ninety degrees. Then you will find warmth in one hand and cold in the other. To the hand which had been immersed in the water at thirty-two degrees, the water at ninety degrees will feel hot; and to the hand which had been immersed in the water at two hundred degrees, the water at ninety degrees will feel cool. If, therefore, the touch in this case be trusted, the same water will be judged to be hot and cold at the same time.