1906.] Main Source of " Precipitable" Substance, etc. 303 



Table V. — Secondary Interactions. Experiment III. 



No. 



Precipita in A series 

 ( + egg white). 



Precipita in B series 

 ( + antiserum) . 





mm. 



mm. 



1 







2 



2 







2 



3 



0-5 



0-5 



4 



1 



3 



5 



1 



0-3 



6 



1 



None 



Among the data afforded by this experiment may be indicated (1) the 

 complete neutralisation of the precipitin in the first two tubes only, and 

 the coincidence of this point with the maximum precipitate obtainable in 

 the primary interactions from O01 gramme of this antiserum ; (2) the 

 inappreciable exhaustion of the homologous proteid as a result of the primary 

 interactions ; and (3) the coexistence of uncombined egg white and its 

 antiserum in the clear superfluids after the primary interactions are 

 completed. 



When larger amounts of egg antiserum were employed, correspondingly 

 larger precipita were obtained, the masses of which were still more strikingly 

 incompatible with an origin from the homologous proteid available. 



Experiment IV. — To two tubes, each containing 1 c.c. of fluid antiserum 

 (approximately equivalent to O'l gramme dried) prepared by injection of 

 fluid egg white, there was added O'l c.c. of 10-per-cent. fresh egg white in 

 salt solution (equivalent to - 0012 gramme dried) and O'l c.c. of 1-per-cent. 

 fresh egg white in saline (0 - 00012 gramme dried) respectively. The pre- 

 cipitates were read in 48 hours, with the results shown in Table VI. 



Table VI. — Primary Interactions. Experiment IV. 



No. 



Amount of egg white 

 in grammes. 



Amount of antiserum 

 in grammes. 



Precipita in 

 48 hours. 









mm. 



1 



-0012 



o-i 



7 (compact) 



2 



-00012 



o-i 



11 (looser) 



The precipitate in Tube No. 2 decreased to 9 mm. on the third day, and, 

 though kept under observation up to the seventh day, it did not shrink 

 below 8"5 mm. The same amount of egg albumin (0"00012 gramme dried) 

 when precipitated by trichloracetic acid would yield a deposit not exceeding 



