Il8 LOCAL ILSSUE REACTIVLIY 



Table vi 



CONCENTRATION AND PURIFICATION OF ANTITYPHOID 

 HORSE SERA 



The chemical studies were done in the laboratory of Dr. H. 

 Sobotka, as follows: 



The plasma or serum was diluted to ii4 times its original 

 volume with distilled water. Instead of a saturated ammonium 

 sulphate sohuion, a 47.5 per cent sodium-magnesitmi sulphate 

 solution was used as the protein precipitant to facilitate the nitro- 

 gen analysis. Twenty-eight parts of this solution ^vere added to 

 72 parts of the diluted serum. The precipitate which contained 

 fibrinogen and part of the euglobidin was discarded. Then a suf- 



