1888 — 89 .] Haycraft and Duggan on Coagulation by Heat. 365 
sulphate, the precipitated globulin filtered off ; by this means one 
obtains a solution of serum albumen in a saturated solution of 
magnesium sulphate. It would have been useless to dilute this 
solution with water, for, in that case, both the albumen and the 
magnesium sulphate would suffer dilution. Dilution was effected 
by the addition of a saturated solution of magnesium sulphate. 
Vitellin, 
Serum alb. (mag. sulph.), 
Hydrocele fluid, . 
Serum globulin, . 
Egg albumen, 
Fig. 1. — Showing the Temperature at which certain Albumens coagulate when 
diluted with One, Two, Three, and Four Volumes of Fluid. 
(a) Undiluted serum albumen, saturated with magnesium sul- 
phate, becomes opalescent at 77° C., and coagulates at 79° C. 
( b ) The same solution, diluted with one volume of a saturated 
watery solution of magnesium sulphate, becomes opalescent at 79° C., 
and coagulates at 82° C. 
(c) When diluted with two volumes, opalescence occurs at 79° C., 
and coagulation at 83° C. 
(d) When diluted with three volumes, opalescence begins at 
81° C., and coagulation at 84° C. 
