446 OF ABSORPTION AND SANGUIFICATION. 



supply; and the function of the cutaneous and pulmonary surfaces may be 

 considered as rather that of exhalation, than of absorption. 1 But there are 

 peculiar conditions of the system, in which the imbibition of fluid through these 

 surfaces is performed with great activity, supplying what would otherwise be a 

 most important deficiency. It may take place either through the direct appli- 

 cation of fluid to the surface, or even through the medium of the atmosphere, 

 in which a greater or less proportion of watery vapour is usually dissolved. 

 This absorption occurs most vigorously, when the system has been drained of 

 its fluid, either by an excess of the excretions, or by a diminution of the regular 

 supply. 



468. It may be desirable to adduce some individual cases, which will set this 

 function in a striking point of view ; and those may be first noticed, in which 

 the Absorption took place through the contact of liquids with the skin. It is 

 well known that shipwrecked sailors, and others, who are suffering from thirst, 

 owing to the want of fresh water, find it greatly alleviated, or altogether relieved, 

 by dipping their clothes into the sea, and putting them on whilst still wet, or 

 by frequently immersing their own bodies. 3 Dr. Currie relates the case of a 

 patient laboring under dysphagia in its most advanced stage ; the introduction 

 of any nutriment, whether solid or fluid, into the stomach, having become per- 

 fectly impracticable. Under these melancholy circumstances, an attempt was 

 made to prolong his existence, by the exhibition of nutritive enemata, and by 

 immersion of the body, night and morning, in a bath of milk and water. Dur- 

 ing the continuance of this plan, his weight, which had previously been rapidly 

 diminishing, remained stationary, although the quantity of the excretions was 

 increased. How much of the absorption, which must have been effected to 

 replace the amount of excreted fluid, is to be attributed to the baths, and how 

 much to the enemata, it is not easy to say; but it is important to remark that 

 " the thirst, which was troublesome during the first days of the patient's 

 abstinence, was abated, and, as he declared, removed by the tepid bath, in 

 which he had the most grateful sensations/' " It cannot be doubted," Dr. 

 Currie observes, " that the discharge by stool and perspiration exceeded the 

 weight of the clysters;" and the loss by the urinary excretion, which increased 

 from 24 oz. to 36 oz. under this system, is only to be accounted for by the 

 cutaneous absorption. 3 Dr. S. Smith mentions that a man, who had lost nearly 

 3 Ibs. by perspiration, during an hour and a quarter's labor in a very hot atmo- 

 sphere, regained 8 oz. by immersion in a warm bath at 95, for half an hour. 4 

 The experiments of Dr. Madden 5 on his own person show that a positive 

 increase usually takes place in the weight of the body, during immersion in the 

 warm bath, even though there is at the same time a continual loss of weight by 

 pulmonary exhalation, and by transudation from the skin. 6 This increase was, 



' We have a remarkable exception to this general statement, however, in the case of 

 Frogs and other Batrachia, which are characterized by the softness of their skins and the 

 thinness of their epidermic covering ; for cutaneous absorption seems in them to be no less 

 active than their cutaneous exhalation and respiration are well known to be. Thus Frogs, 

 which habitually live in a moist atmosphere, seldom or never drink ; yet when they have 

 lost fluid by exposure to hot dry air, they will regain their weight by being left for a time 

 upon moist sand ; and the bladder, which serves as a reservoir of water for cutaneous 

 exhalation, though previously emptied, will be refilled. 



2 See a collection of such cases in Dr. Madden's " Experimental Inquiry into the Phy- 

 siology of Cutaneous Absorption," p. 47. 



3 "Medical Reports," vol. i. pp. 308326. 4 "Philosophy of Health," vol. ii. p. 396. 



5 Op. cit., pp. 5963. 



6 That part of the function of cutaneous transpiration, which consists in simple exhala- 

 tion, is of course completely checked by such immersion ; but that which is the result of 

 an actual secreting process in the cutaneous glands (CHAP. xii. SECT. 4) is increased by 

 heat, even though this be accompanied with moisture. 



