CHEMICAL NATURE OF SKIN SECRETIONS. 
671 
the breaking out of sweat, the excretion of carbon dioxide by the skin 
is also suddenly increased, a fa it probably related to the increased 
activity of the gland-cells : — 
Excretion of Water and Carbon Dioxide by the Skin at various Temperatures 
of Surrounding Air. 
(Separate experiments on same individual, naked, in a Pettenkofer and Voit's chamber). 1 
Temperature of 
Chamber. 
Water Excretion 
(Onus, per Hour). 
Water Excretion 
(Onus, per Twenty- 
four Hours). 
Carbon Dioxide 
(Onus, per Hour). 
Carbon Dioxide 
(Onus, per Twenty- 
four Hours). 
29°-8 C. 
22 '2 
532-8 
•37 
8-9 
30-4 ., 
27-8 
667-2 
•40 
9-6 
31°-5 ,, 
71-9 
1725-6 
•37 
8-9 
3r-9 ,, 
50-3 
1207-2 
•35 
8-4 
32° -8 „ 
73-4 
1761-6 
•35 
8-4 
33°-8 ,, 
82-6 
1982-4 
•87 
20-9 
35°'4 ,, 
106-8 
2563-2 
1-04 
25-0 
35° -7 ,, 
107-0 
2568-0 
•9 
21-6 
38 :, 4 .. 
158-8 
3811-2 
1-23 
295 
The sweat of man is a colourless, opalescent liquid of salt taste, 
poorest in solids of all the secretions, though richest in salts in relation 
to organic solids. 
Sweat is acid in reaction, even when collected from the palm of the 
hand, where there is no danger of admixture of sebaceous secretion. 2 
This acidity is probably due to volatile fatty acids, which may be 
subserp^ently driven off, leaving an alkaline reaction at the surface of 
the skin. 3 In profuse sweating the acidity may give way to neutrality, 
followed later by alkalinity. 4 
In 1000 parts. Favre. 
Schottin. 
Funke. 
Water .... 
995-573 
977-40 
988-40 
Solids 
4-427 
22-60 
11-60 
Epithelium 
4-20 
2-49 
Fat . 
•013 
Lactates 
•317 
Sudorates . 
1-562 
Extractives 
•005 
11-30 
Urea . 
•044 
1'55 
Sodic chloride 
2-230 
3-60 
Potassic chloride 
•024 
Sodic phosphate 
Traces 
1-31 
Alkaline sulphates 
•011 
•39 
Earthy phosphates 
Traces 
Total salts . 
7-00 
4-36 
Note to Table. — The sudoric or hidrotic acid of Favre has not been found by any 
subsequent observers. He gives the empirical formula, C 10 H 1G H. 2 O 13 . Lactic acid also 
has not been found by any other observer. 5 
1 Schierbeck, loc. cit. 
- Francois- Franck, "Diet, encycl. d. sc. med.," Paris, 1884, Ser. 3, tome xiii. p. 51, 
Art. "Sueur." 
3 Tourton, "These de Lyon," 1879, No. 24, Ser. 1. 
4 Favre, loc. cit. ; Triimpy and Luchsinger, Arch. f. d. ges. Physiol., Bonn, 1878, 
Bd. xviii. S. 494. 
5 For analysis of sweat of a rheumatic patient, see Harnack, Fortschr. d. Med. , Berlin, 1 893, 
S. 91 ; also Hermann, Jahresb. ii. d. Fortschr. d. Anat. u. Physiol., Leipzig, 1895. Bd. ii. 
S. 226. 
