396 PROTEIN POISONS 



addition, after standing for twenty-four hours in the incu- 

 bator, was diluted to 10 c.c. with normal salt solution and 

 deprived of normal proteins by acetic acid and heat. The 

 filtrate gave a slight biuret test but no Millon. At 11.15, 

 2.5 c.c. of the filtrate was injected intracardiacally into a 

 guinea-pig. Temperature before the injection was 98.8. 

 At 11.30, 97.9 and at 11.40, 98.4. The animal was not 

 visibly disturbed, with the exception of slight tremor. 



A second sample of 2 c.c. of this serum which had been 

 mixed with 2 c.c. of milk and kept in the incubator for 

 twenty-four hours was treated in the same way. The biuret 

 was slight and the Millon negative. The guinea-pig was 

 not disturbed nor the temperature lowered. 



A third portion of the serum mixed with an equal volume 

 of a 2 per cent, solution of Witte's peptone was tested in 

 the same way. The filtrate gave a beautiful biuret, but 

 no Millon. The temperature of the pig fell 2.6 in ten 

 minutes, but otherwise the animal was not affected. 



A fourth portion of the serum mixed with an equal 

 volume of a dilution of egg-white was tested in the same 

 way. The filtrate gave a splendid biuret and also a good 

 Millon. The pig received only 1.25 c.c. of the filtrate, half 

 the quantity given to the others, but it immediately 

 developed the symptoms characteristic of the protein 

 poison and died within five minutes. Postmortem examina- 

 tion showed no injury and the heart-apex still beating. 



We took a mixture of 2 c.c. of the fever serum and 10 c.c. 

 of the egg-white dilution (1 to 1), which had stood in the 

 incubator for five days. This was diluted to 20 c.c. and 

 heated, after being made distinctly acid with acetic acid. 

 After the removal of the normal blood proteins the filtrate 

 gave both the biuret and the Millon tests very distinctly. 

 Five cubic centimeters of the filtrate was evaporated on 

 the water-bath and the yellowish residue extracted with 

 20 c.c. of absolute alcohol. The portion insoluble in alcohol 

 was extracted with 5 c.c. of salt solution. The part soluble 

 in salt solution responded feebly to both the biuret and the 

 Millon tests. The part insoluble in both alcohol and salt 



