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XIV. Appendix to a paper on the Variations of the Acidity of the Urine in the state 
of Health. 
By Henry Bence Jones, M.D.,M.A. Cantab. ,F.R.S., Physician to St. Georges Hospital. 
Received May 7, — Read May 24, 1849. 
On the Influence of Caustic Potash, Tartaric Acid, and Tartrate of Potash on the 
Acidity of the Urine. 
In a paper on the variations of the acidity of the urine in the state of health, I have, 
in the third section, given the effect of dilute sulphuric acid ; in this Appendix I pur- 
pose to show the influence of other medicines on the variations of the acidity of the 
urine. 
III. (&.) The effect of caustic potash on the acidity of the urine was examined. 
The caustic potash of pharmacy varying much in its specific gravity from 1060 
downwards, and in the proportion of carbonate of potash which it contains, some 
caustic potash perfectly free from carbonate, and of specific gravity 1072, containing, 
by Dr. Hofmann’s analysis, from 6*20 to 6'29 per cent, of potash, was used for the 
following experiments. It was taken in distilled water. 
The day before the alkali was begun the variations of the acidity of the urine were 
first determined for the purpose of comparison. 
The first day two drachms and a half of caustic potash were taken ; the same 
quantity the second day, and the third day three drachms were taken. Thus eight 
drachms were taken in three days ; and the following day, when no caustic potash 
was taken, the variations of the acidity of the urine were again determined for the 
purpose of further comparison. 
(20.) The day previous to the alkali. Breakfast on eggs, meat, coffee and bread, at 
8** 5“ A.M. Dinner on mixed diet at 6*“ p.m. Water passed at f 1 S'” a.m. was thrown away. 
h 
m 
Spec. gr. 
Acidity per 1000 grains of urine. 
Appearance. 
Water passed at 8 
5 a.m. 
= 1023-2 
= -f 25-41 measures. 
Thick from urates. 
Water passed at 9 
30 
= 1022-8 
= +12-61 
Thick from urates. 
Water passed at 10 
45 
= 1024-1 
= - 4-88 
Clear. 
Water passed at 11 
35 
= 1027-0 
= -13-63 
Clear. 
Water passed at 12 
35 P.M. 
= 1026-5 
= - 3-89 
Clear. 
Water passed at 2 
30 
= 1025-0 
= + 14-72 
Clear. 
Water passed at 4 
15 
= 1024-4 
= +20-49 
Clear. 
Water passed at 6 
0 
= 1026-6 
= + 31-17 
Thick from urates. 
Water passed at 9 
0 
= 1028-6 
= +18-47 
Clear. 
Water passed at 11 
0 
= 1028-0 
= -11-67 
Clear. 
From this it appears that the variations are nearly alike to those which were 
2 M 
MDCCCXLIX. 
