ABSORPTION THROUGH THE CUTANEOUS SURFACE. 513 



ever, the special function of the latter is so much exalted, that itusually super- 

 sedes the necessity of any other supply ; and the function of the cutaneous 

 and pulmonary surfaces may be considered as rather that of exhalation, than 

 of absorption. 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 application 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 vigour- 

 ously, when the system has been drained of its fluid, either by an excess of 

 the excretions, or by a diminution of the regular supply. 



677. 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. Dr. Currie relates the 

 case of a patient labouring under dysphagia in its most advanced stage; the 

 introduction of any nutriment, whether solid or fluid into the stomach, having 

 become perfectly impracticable. Under these melancholy circumstances, an 

 attempt was made to prolong his existence, by the exhibition of nutritive ene- 

 mata, and by immersion of the body, night and morning, in a bath of milk and 

 water. During 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 in- 

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

 by the cutaneous absorption. Dr. S. Smith mentions that a man, who had 

 lost nearly 3 Ibs. by perspiration, during an hour and a quarter's labour in a 

 very hot atmosphere, regained 8 oz. by immersion in a warm bath at 95, for 

 half an hour. The experiments of Dr. Madden* 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 pul- 

 monary exhalation, and by transudationt from the skin. This increase was, 

 in some instances, as much as 5 drachms in half an hour ; whilst the loss of 

 weight during the previous half hour had been 6| drachms: so that, if the 

 same rate of loss were continued in the bath, the real gain by absorption must 

 have been nearly an ounce and a half. Why this gain was much less than 

 in the cases just alluded to, is at once accounted for by the fact that there was 

 no deficiency, in the latter case, of the fluids naturally present in the body. 



678. The quantity of water which may be imbibed from the vapour of the 

 atmosphere, would exceed belief, were not the facts on which the assertion 

 rests, beyond all question. Dr. Dill relates the case of a diabetic patient, 



' Prize Essay on Cutaneous Absorption, pp. 50 63. 



f That part of the function of cutaneous transpiration, which consists in simple exhalation , 

 is of course completely checked by such immersion ; but that which is the result of an actual 

 secreting process in the cutaneous glands (CHAP, xv., Sect. S) is increased by heat, even 

 though this be accompanied with moisture. 



