CUTANEOUS ABSORPTION. 53 



euticle ; and it is universally admitted that when this 

 obstacle is removed, the process goes on with great 

 vigour. Thus arsenic applied to cancerous sores, 

 and strong solutions of opium to extensive burns in 

 children, have been absorbed in quantities sufficient 

 to poison the patients. Colic in its severest forms 

 has followed similar external applications of the 

 salts of lead. Mercury, also, in the form of fumiga- 

 tion, has often been used where rapid action was 

 required, because in the state of vapour it is very 

 speedily taken up by the cutaneous absorbents. 



It is quite certain, then, that the skin does absorb. 

 The only doubt is as to what extent the cuticle oper- 

 ates in preventing or modifying that action. When 

 friction accompanies the external application, the 

 cuticle, as we see exemplified in the use of mercu- 

 rial and other liniments, is not an efficient obstacle. 

 But when friction is not resorted to, and the sub- 

 stance applied is of a mild unirritating nature, such 

 as oil, it may remain in contact with the skin for a 

 long time without being taken into the system in 

 appreciable quantities. If, however, it is irritating, 

 like Spanish flies, absorption speedily begins, and is 

 carried on through the cuticle, as is proved by the 

 effects produced on the urinary organs. 



When the perspiration is brought to the surface 

 of the skin, and confined there either by injudicious 

 clothing or by want of cleanliness, there is much 

 reason to suppose that its residual parts are again 

 absorbed, and act on the system as a poison of 

 greater or less power, according to its quantity and 

 degree of concentration, thereby producing fever, 

 inflammation, and even death itself; for it is estab- 

 lished by observation, that concentrated animal 

 effluvia form a very energetic poison. The fatal 

 consequences which have repeatedly followed the 

 use of a close water-proof dress by sportsmen and 

 others, and the heat and uneasy restlessness which 

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