1888 - 89 .] Haycraft and Duggan on Coagulation by Heat. 367 
The Effect of Dilution on the Coagulation Point of Vitellin. 
The yolks of several eggs were dissolved in 6 per cent, solution 
of sodium chloride and filtered. The filtrate was poured into a large 
volume of distilled water, the precipitate of vitellin redissolved in 
saline solution, reprecipitated in distilled water, and dissolved in 
5 per cent, solution of sodium chloride. In this case the vitellin, 
prepared from six eggs, was dissolved in 300 c.c. of the solution. 
In order to study the effect of dilution, a 5 per cent, solution 
of sodium chloride was added in all cases. 
(a) The vitellin solution became opalescent when heated to 
80° C., and coagulated at 85° C. 
(b) When diluted with one volume of 5 per cent, solution of 
sodium chloride, the vitellin became opalescent at 81° C., and 
coagulated at 85° ’5 C. 
(c) When diluted with two volumes, it became opalescent at 
82° C., and coagulated at 86°*5 C. 
(d) When diluted with three volumes, it became opalescent at 
82° C., and coagulated at 87° C. 
(e) When diluted with four volumes, it became opalescent at 
83° C., and coagulated at 88° C. 
The experiment was repeated, giving a result almost precisely the 
same. It will be noticed that in this proteid the coagulation point 
does not vary to a very considerable extent with dilution. 
The Effect of Dilution on the Coagulation Point of Serum Globulin. 
The coagulation point of serum globulin is given by Halliburton 
as 75° C. (Reference 6, p. 163). 
In the first experiment the globulin was precipitated from 
bullock’s blood by magnesium sulphate. The precipitate was, after 
washing, dissolved in a 5 per cent, solution of magnesium 
sulphate. It was diluted with a 5 per cent, watery solution of 
magnesium sulphate. Unfortunately the opalescence was not noted 
down. The flocculi were well marked. 
(a) The solution of serum globulin in a 5 per cent, solution of 
magnesium sulphate coagulated at 74° C. 
(b) The solution, when diluted with an equal volume of 5 
