1888-89.] Haycraft and Duggan on Coagulation by Heat. 373 
however, justified in speaking of magnesium sulphate as lowering 
the coagulation point of albumen by its presence. 
It is a point of some interest to discover whether a salt, which, by 
its addition to an albuminous solution, raises the temperature at 
which coagulation occurs, will produce the same result on an albu- 
minous solution already saturated with another salt. This we have 
determined to some extent. 
Effect of the Addition of various Salts on the Coagulation Point of 
Egg Albumen already saturated ivith Magnesium Sulphate. 
Egg albumen was diluted with two volumes of water, and saturated 
with magnesium sulphate. The solution was filtered, and it was 
found on heating to become opalescent at 79° C., coagulating at 
81 0, 75 0. The salts added, most of which have already been 
studied in respect to their action on the coagulation point of egg 
albumen (Table I.), are seen to lower the coagulation point of egg 
albumen saturated with magnesium sulphate. 
Table II. showing the Action of various Salts upon the Coagulation 
Point of Egg Albumen already saturated with Magnesium 
Sulphate. 
Salt added. 
Proportion. 
Opalescence. 
Flocculi. 
Albumen saturated with magne- 
Per cent. 
°C. 
°C. 
.• 
sium sulphate , 
6 
79 
8175 
Sodium chloride, 
6 
72 
79 
Sodium iodide, .... 
6 
70 
Sodium sulphate, 
6 
79 
81-5 
Potassium chloride, . 
6 
72 
79 
Potassium bromide, . 
6 
70 
74 
Potassium nitrate, 
Potassium chlorate, . 
6 
70 
73-75 
6 
71 
74-5 
Potassium sulphate, . 
6 
74 
77 
Ammonium chloride, . 
6 
62 
73 
Ammonium nitrate, . 
6 
i 
63 
65 
On comparing this table with that on page 370, it will be noted, 
first, that those salts which on Table I. do not raise the coagulation 
point of egg albumen to any great extent, NaCl, KC1, K 2 S0 4 , and 
Xa 2 S0 4 (Yarenne), do not lower the coagulation point (Table II.) 
to any great extent. On the other hand, salts like KBr, K 2 ND 3 , 
and NH 4 N0 3 , which raise the coagulation point in Table I., depress 
