Journal of Agricultural Research v 0 i. xxix, No. 10 
472 
by appropriate treatment with am¬ 
monium sulphate. The precipitated 
fractions were dissolved separately 
and the salts removed by dialysis. 
After dialysis, NaCl in an amount 
sufficient to make a concentration of 
0.9 per cent was added to each dialyzed 
fraction. As the volumes of these 
fractions were unequally increased by 
dialysis, identical concentrations of 
the separate proteins unfortunately 
were not obtained. The solutions thus 
obtained were examined on ’ the day 
before the formaldehyde was added, 
and on the tenth, eighteenth, sixtieth, 
and ninety-fifth days thereafter. On 
the sixtieth day the amount of formal¬ 
dehyde in the albumin fraction was 
increased to 0.37 per cent and on the 
ninetieth day to 0.74 per cent. The 
results of the examination are reported 
in Table I. 
It is to be noted that the concentra¬ 
tion of proteins in the albumin fraction 
was lower than in any of the other 
fractions. This test suggests that 
albumins, in the presence of formalde¬ 
hyde, probably pass through the stage 
of solubility corresponding to pseudo¬ 
globulins before the stage correspond¬ 
ing to euglobulins 4 is reached. 
This experiment has been repeated 
several times under practically the 
same conditions, and in each instance 
the results confirmed those presented 
above. The several experiments of 
this study may be summarized as 
follows: In the presence of 0.18 per 
cent formaldehyde pure native pseudo¬ 
globulins behaved as if they were con¬ 
verted into euglobulins, and pure 
native albumins as if converted into 
pseudoglobulins, but euglobulins were 
not produced from albumin solutions 
Table I.— The effect of formaldehyde on the precipitation limits of pure globulins 
and albumins 
Protein fraction 
Euglobulin_ 
Pseudoglobulin 
Albumin 
• Before the formaldehyde was added. 
b The amount of formaldehyde was increased. 
The euglobulin fraction before treat¬ 
ment contained a small amount of 
native pseudoglobulins and in this 
fraction gratification occurred by the 
tenth day. In the pseudoglobulin 
fraction there was an increase in the 
formed euglobulins throughout the 
duration of the experiment. In the 
albumin fraction with 0.18 per cent of 
formaldehyde there was a progressive 
increase in the protein designated as 
pseudoglobulins, but even after 60 days 
there was no appearance of formed 
euglobulins; however, on increasing 
the formaldehyde in this fraction to 
0.74 per cent on the ninetieth day there 
was a production of formed euglobulins. 
Grams per 100 c. c. 
Time of 
contact 
Euglobu- Pseudo- 
lins globulins 
Albu¬ 
mins 
Days 
« 0 
10 
1.86 
Gelled. 
0.45 
0.00 
a 0 
10 
18 
60 
*0 
10 
6 60 
b 90 
95 
.08 
.50 
1.60 
2.12 
.00 
.00 
.00 
2.78 
2.36 
1.26 
.74 
. 15 
.36 
.80 
.00 
1.73 
1. 52 
1.08 
No examination was made. 
.52 ! 
.38 
containing only 0.18 per cent formal¬ 
dehyde. With greater amounts of 
formaldehyde, euglobulins were pro¬ 
duced from albumins. 
THE ORDER OF THE REACTION AS 
DETERMINED BY THE VELOCITY 
OF THE REACTION 
In the paper previously mentioned, 
it was indicated that the velocity of the 
reaction involved in the formation of 
euglobulins in formolized serum was 
controlled by the concentration of the 
reacting substances, namely, the pro¬ 
teins of the serum on the one hand and 
the formaldehyde on the other. This 
* Throughout this paper the unmodified term “euglobulins” is used to refer to any protein which is pre- 
cipitable by one-third saturated ammonium sulphate whether it was originally present in the serum or 
was formed by the action of formaldehyde on serum proteins. 
