518 DISEASES OF THE SKIN. 



lishment of the perspiration may act beneficially upon disease so in- 

 duced. The utmost objection that can be made against the statement, 

 that " suppression of the perspiration has caused illness," is, that it is 

 too indefinite ; since we are quite ignorant as to why it is that the 

 chilling of a perspiring body so often gives rise to disease. Hence, I 

 consider it to be entirely warrantable, when it has been proved, or 

 even when it is* very probable, that the cessation of an habitual hyperi- 

 drosis of the feet has been followed by sickness, that we should attempt, 

 by means of hot stimulating foot-baths and by warmly clothing the 

 feet, and by sprinkling the stockings with flour of mustard, to reestab- 

 lish copious diaphoresis of the extremities. I do not mean by this, 

 that persons suffering from offensively-perspiring feet and armpits are 

 to be forbidden to wash and bathe, or to use cold water for the pur- 

 pose. On the contrary, the judicious use of cold baths and of cold 

 washing, so far from being hurtful, is of the utmost benefit to persons 

 who perspire too freely, and who are liable to take cold. In fact, I 

 think it probable and by no means inconsistent with the opinions ex- 

 pressed above, that the cautious checking both of local and general 

 hyperidrosis is the best means of obviating the danger of catching cold 

 by which it is accompanied. At all events, people with sweating feet 

 should frequently change their shoes and stockings. When the epi- 

 dermis becomes soft and pasty from maceration, and when it inclines 

 to peel off, exposing the rete Malpighii, making it painful and difficult 

 for the patient to walk, Hebra recommends, as an excellent remedy, 

 that the soles and toes should be smeared for some days with the un- 

 guentum diachyli, and then be wrapped in linen rags. He claims 

 that, by this treatment, not only does a new and firmer layer of epi- 

 dermis take the place of the old and softened one, but it causes a dim- 

 inution of the hyperidrosis for some time afterward. I have no ex- 

 perience of my own testifying to the efficacy and harmlessness of this 

 procedure. 



We have already mentioned that a diminution of the cutaneous 

 secretions may form one of the symptoms of senile marasmus. In 

 other instances, as has already been mentioned, it depends upon de- 

 rangement of innervation ; in others, again, it is due to disease of the 

 skin, to psoriasis or to ichthyosis, while, finally, cases exist of anidrosis 

 and now and then even anidrosis of half the body, the causes of which 

 are quite unknown. 



With regard to the qualitative alterations of the perspiration, the 

 presence of biliary pigment in the sweat of persons with icterus, upon 

 which the yellow stain of their clothing depends, is perhaps the best 

 known. JBarensprung, however, believes that the vehicle of the pig- 

 ment is not the liquid of the perspiration, but the epithelial cells which 



