438 THE SKIN. 



because the skin loses water by evaporation. But, from 

 the result of many experiments, it may now be regarded 

 as a well- ascertained fact that such absorption really occurs. 

 M. -Edwards has proved that the absorption of water by 

 the surface of the body may take place in the lower 

 animals very rapidly. No If only frogs, which have a thin 

 skin, but lizards, in which the cuticle is thicker than in 

 man, after having lost weight by being kept for some 

 time in a dry atmosphere, were found to recover both their 

 weight and plumpness very rapidly when immersed in 

 water. When merely the tail, posterior extremities, and 

 posterior part of the body of the lizard were immersed, the 

 water absorbed was distributed throughout the system. 

 And a like absorption through the skin, though to a less 



xtent, may take place also in man. 



Dr. Madden, having ascertained the los"s of weight, by 

 cutaneous and pulmonary transpiration, that occurred 

 during half an hour in the air, entered the bath, and 

 remained immersed during the same period of time, breath- 

 ing through a tube f which communicated with the ail- 

 exterior to the room. He was then carefully dried and 

 again weighed. Twelve experiments were performed in 

 this manner; and in ten there was a gain of weight, 

 varying from 2 scruples to 5 drachms and 4 scruples, or a 

 mean gain of I drachm 2 scruples and 13 grains. The 

 loss in the air during the same length of time (half an 

 hour) varied in ten experiments from 2\ drachms to 



I ounce 2| scruples, or in the mean was about 6\ drachms. 

 So that, admitting the supposition that the cutaneous 

 transpiration was entirely suspended, and estimating the 

 loss by pulmonary exhalation at 3 drachms, there was, in 

 these ten experiments of Dr. Madden, an average absorp- 

 tion of 4 drachms, I scruple, and 3 grains, by the surface 

 of the body, during half an hour. In four experiments 

 performed by M. Berthold, the gain in weight was greater 

 than in those of Dr. Madden. ' 



