ORGANIC 
matters. The analysis must afterwards be pro- 
ceeded with upon the principles already laid 
down, being first directed to the soluble ingre- 
dients and then to the insoluble matters. 
C. ProximaTr ANALYSIS OF INDIVIDUAL 
SECRETIONS. 
1. Of the urine. 
The following is a detailed example of the 
method of analysing healthy urine:— 
As there was abundance of the fluid for exa- 
mination, fresh portions were taken whenever 
it seemed desirable to do so for determining 
any particular ingredient. 
* The secretion had a sp. gr. of 1020.4. It 
distinctly reddened litmus paper, and exhi- 
bited a slight cloud of floating mucus. 
(@) 3200 grs. were filtered through a weighed 
filter, and the mucus collected. It amounted 
to 0.53 grs. 
3200 : 1000 : : 0.53 : 2 (= 0.165) mucus. 
(b) 200 grs. evaporated in a counterpoised 
capsule left 8.64 grs. 
200 : 1000 : : 8.64 : # (= 43.2) solid mat- 
ters. 
1000 — 43.2 = 956.8 water. 
_ (©) The residue, 8.64 after evaporation, ig- 
nited in the capsule left 2.36 grs. of saline 
matter. 
200 : 1000 : : 2.36 : w (= 11.8) fized salts. 
(d) 1000 grs. of urine (freed from mucus by 
filtration) was evaporated to dryness in a pla- 
tinum capsule. It was treated with water, 
acidulated with hydrochloric acid, and left 
0.37 grs. of uric acid; after incineration of the 
uric acid a trace of silica remained. 
(e) During the last three years I have made 
Many careful analyses of the urine with express 
attempts to obtain from it the lactic acid it 
is said to contain; but though I employed 
various methods, and in some instances large 
eras of urine, I have never succeeded in 
eliminating it from fresh urine, and I therefore 
(as the methods used were capable of detecting 
small quantities of the lactates when purposely. 
mingled with the urine) concluded that lactic 
acid is not a normal constituent of human 
urine. Liebig has lately stated the same fact 
founded on his own recent examinations of the 
ecretion. 
(7) 1000 grs. of urine were evaporated to 
dryness and exhausted with alcohol. This 
Icoholic solution was evaporated, the dry mass 
reated with water, and nitric acid added, 
ith the precautions already mentioned, fur- 
aished 29.17 grs. of nitrate of urea. 
100 : 29.17 : : 48.78: « (= 14.23) urea. 
_(g) The residue after exhaustion with alco- 
aol weighed 6.6 grs. It was ignited, and left 
Saline mass, amounting to 4.46 grs. 
6.6—4.46 = 2.14 organic matter. 
‘rom this we deduct the uric acid 0.37 (d), and 
acus 0.165 (a), the residue 1.605, is “ watery 
wtract. 
(h) The portion soluble in alcohol amounts 
».43.2—6.6, or 36.6 grs., which we find com- 
osed as follows: 
The total saline matter of the urine (in- 
uding the sulphuric acid volatilized by igni- 
on (r)) 
ANALYSIS. 807 
amounts to, .13.388 grs. (= 11.8 + 1.588) 
deduct .... 4.46 salts insoluble in 
alcohol (g) 
remain .... 8.928 salts dissolved by 
alcohol. 
fixed salts .... 8.928 
UFEA seoeeeee 14.230 by (f) 
mur.ammonia 0.915 by (v) 
24.073 
36.6 —24.073= 12.527 alcoholic extract. 
The composition of the urinary salts has now 
to be determined. 
(2) 1000 grs. of urine were acidulated with 
nitric acid, and mixed with a solution of ni- 
trate of silver, an abundant precipitate of 
chloride of silverensued. 
The filter with the precipitate weighed 39.13 
The filter alone.....scccesscecevs 15.23 
Total wt. of the chloride before fusion 23.90 
23.12 of chloride fused in a counterpoised 
porcelain capsule gave 19.12 grs., weight of 
chloride after fusion. 
23.12 : 23.90 :: 19.12: # (= 19.77) fused 
chloride silver. 
100 : 19.77 : : 25: a (= 4.942) chlorine. 
(k) The filtered liquid was treated with 
nitrate of baryta, the precipitate collected, well 
washed with boiling water, ignited, weighed 
4.97 grs. 
100 : 4.97 : : 34.19 : x (= 1.702) sulphuric 
acid, 
(2) 1000 grs. of urine were supersaturated 
with ammonia; a bulky precipitate of the 
earthy phosphates fell, which after ignition 
weighed 0.65 grs. 
(m) The filtered liquid supersaturated with 
lime-water gave a precipitate, which weighed 
after ignition 3.57 grs. : 
100 : 3.57 : : 49.1 : w (= 1.753) phosphoric 
acid, which is in combination with al- 
kaline bases. 
To determine the bases a considerable por- 
tion of urine was evaporated, and the residue 
burned to whiteness. 
(n) 41.5 grs. of the saline residuum left 
2.45 grs. insoluble in water. 
41.5 —2.45 = 39.05 alkaline salts. 
41.5 : 11.8 (c):: 2.45 : 0.6956 insoluble 
salts in 1000 urine; by (1) we found the 
earthy phosphates 0.65. 
11.8 — 0.7 = 11.1 alkaline salts per 1000 
urine. 
(0) The insoluble portion dissolved in a little 
nitric acid, supersaturated with ammonia and 
redissolved in acetic acid, gave by oxalate of 
ammonia a precipitate which yielded on igni- 
tion 1.32 grs. carbonate of lime. 
2.45 : 0.6956 :: 1.32 : x (= 0.3753) carb. 
lime. 
100 : 0.3753 : : 56 : x (= 0.2101) lime. 
(p) The solution filtered from the oxalate of 
lime and supersaturated by ammonia gave, on 
agitation followed by repose for some hours, 
a crystalline precipitate, weighing 1.18 grs, 
after ignition. 
“ 
