New York AGRICULTURAL EXPERIMENT STATION. 243 
Taste XI.— SHOWING RESULTS oF EXTRACTION OF AcID FROM AciIp CASEIN 








BY WATER. 
L a K L M N O Pp 
gee | *38./S8e./ ged | Bs (sg see 
Og OR Orne a eh n wn 
Of sat lag O | Fe ae oO Boe) 
wee Biel Barter ger q 3) Go 8 oem 
32:3 Or oO Zor Syd =) : ne} Se 
No. oF ExPERI- D Bia ae |2 oa Drak eas . 
@ x : CO}]CL8 ods 3a aH 
MENT. Beep (ed. S) a Bey Se ein mee PSHM TRE ARS Calo = brie BNE 
Beu8 | §udsd ork hot Gus tal od esol 
eos Sigg 35 nas an rin O75 he 235 8° ie 
ZHae Face | Ra gee ga ga wets ig CO oe 
A Oo a Oo Oo O P4 
srs Gee a ae ee 07 (.0327) 3.39 fe) 100.9 102.6 3130.0 
1 Suis ey a ae 1 min. 4594 47.58 44.19 56.9 57.8 126.0 
PS i yp ae 5 min. .5057 | 52.28 | 48.98 52.5 52.9 104.0 
A an ee eae 15 min. -5170 | 53.46.| 50.30 49-9 50.7 98.1 
cs 5 oP We SE ae eee Lr, 5243 54.94 50.27 49.8 50.3 95-9 
DG Seo coe 2 hrs. 5232 54.12 50.93 50.7 Bland 97.8 
Gear ee tek a 5 hrs. .5139 53.22 49.80 51.4 52.2 IoI.5 







The following statements summarize the results embodied in 
Tables X and XI: 
(1) When casein that has taken up acid is treated with water, 
it begins to lose acid rapidly to the surrounding water, and in I 
minute, under the conditions of the experiment, nearly one-half of 
the acid contained in the casein is extracted. 
(2) The acid continues.to pass from the casein into the water 
until a certain ratio is reached between the concentration of acid 
in the casein and the concentration of acid in the surrounding water, 
when equilibrium is established. The ratio is practically the same 
as the one found by treating casein with acid until equilibrium is 
established, the final conditions of temperature, concentration and 
proportions being equal. Compare values of ratios in column P, 
Table XI, with those of Table [IX for three or more hours. 
(3) It makes no difference whether all the acid is in the casein 
or in the water at the start; it divides itself between the two in a 
ratio which, for constant conditions, is constant. 
(4) For illustration and comparison, we can use the results 
embodied in Table IX, Series 3, in which the final conditions of 
temperature, concentration and proportions are nearly the same as 
in the case of the results presented in Table XI. In both cases the 
ratio of concentration of acid in casein to that in water, when 
reached under similar conditions, is practically the same (that is, 
about 97) at the time equilibrium is established. The comparison is 
quite strikingly shown by the curves of Fig. 8, B representing the 
