EXCRETION OF SWEAT 



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2. EXCRETION OF SWEAT 



A. COMPOSITION AND PROPERTIES 



Sweat is the thinnest of all the body fluids, and, when filtered, is clear 

 and colorless, and has a specific gravity of 1.003-1.008. Its reaction to litmus 

 may be acid, neutral or alkaline; its taste is salty; its odor is unpleasant and 

 differs for the different portions of the body. The odor is destroyed by 

 heating it up to 110 C. 



In the following table two analyses of sweat are given. The one by Harnack 

 is taken from the sweat of a rheumatic patient, secreted in one to two hours in 

 a vapor bath; the other by Camerer, Jr., was taken from sweat secreted in an 

 electric-light bath in the course of seventy-five to ninety minutes. 



Human sweat is said to contain also about 0.045 per cent proteid matter and 

 two enzymes, one diastatic and the other proteolytic, as well as ethereal sul- 

 phates, aromatic oxyacids, skatol and creatinin in small quantities. 



According to Arloing, the sweat of a healthy man possesses toxic proper- 

 ties; by intravenous injection of a dose of 10-15 c.c. per kg. of body weight, it 

 kills a dog in fifteen to eighty-four hours. The sweat produced in work is more 

 poisonous than that given off during a vapor bath. Vomiting and congestion 

 of the alimentary canal are mentioned as the most prominent symptoms. Par- 

 ticipation of Bacteria in these phenomena appears to be excluded, because sweat 

 is said to lose only a little of its toxicity by sterilization in the autoclave. 



It has long been known that animals, in which the cutaneous secretions 

 are stopped by means of varnishes, die within a short time; and attempts 

 were made to explain this effect by the retention of products normally given 

 off in the sweat. Then came the conviction that the sweat does not remove 

 any toxic substances from the body, and the influence of the varnish was 

 sought in the great radiation of heat caused by it. It is altogether possible 

 that the increased loss of heat has a certain, probably even a great, signifi- 

 cance. But if the above-mentioned experimental facts with reference to the 

 toxicity of sweat are confirmed, we must again ascribe the most important 

 role to the retention of decomposition products. This view is supported more- 

 over by the fact that varnished animals take only a little food, notwithstand- 

 ing great loss of heat and the increased heat production thereby demanded 



