THE PHENOMENA OF ADSORPTION. 455 



We may add that the previous sensitization of the corpuscles 

 is of considerable importance in respect to the rapidity with which 

 the conglutination and hemolysis appear. Thus we find that in- 

 tense agglutination takes place in from 5 to 7 minutes in tubes 

 12, 13 and 15, in 10 minutes in tube 10 and in about 15 minutes 

 in tubes 3, 4 and 6. The rapidity of hemolysis corresponds. 



The contrast between tubes 1 and 10, 1 and 4, and 1 and 3 is 

 particularly to be noted. 



Similar experiments made with fresh bovine serum give similar 

 results. Inasmuch as alexin fixation follows the fixation of the 

 sensitizer, by placing fresh bovine serum in contact with an 

 equal volume of washed guinea-pig blood for a short period 

 (about 10 minutes at room temperature) we obtain a fluid that 

 is deprived of sensitizer but still contains an appreciable amount 

 of alexin and of conglutinin. Serum treated in this manner has 

 no effect on normal guinea-pig corpuscles, but it does hemolyze cor- 

 puscles that have been previously sensitized by heated bovine serum 

 and subsequently washed, and the hemolysis in this case also is 

 preceded by the characteristic conglutination. In the same way 

 we find that a relatively small dose of fresh intact bovine serum, 

 when added to guinea-pig corpuscles, conglutinates and hemolyzes 

 them more rapidly if they have been previously sensitized and 

 washed. For example, in two tubes, A and B, is placed 0.1 of a 

 cubic centimeter of washed guinea-pig blood and 0.5 of a cubic 

 centimeter of salt solution. To A is then added 0.5 of a cubic 

 centimeter of heated bovine serum. A half hour later the cor- 

 puscles are washed, centrifugalized and the supernatant fluid de- 

 canted; 1 c.c. of salt solution and 0.1 of a cubic centimeter of 

 fresh bovine serum is then added to each corpuscle sediment. In 

 tube A conglutination takes place in 40 minutes and hemolysis in 

 an hour; in B the phenomena occur in 1 and 2 hours respectively. 

 It is certain, then, that guinea-pig corpuscles that have been sub- 

 jected to bovine serum, 56 degrees, fix the sensitizer. 



We may now recall in this connection the fact which we have 

 already mentioned and which at first sight might seem contra- 

 dictory to the preceding statements. If we prepare a mixture 

 containing a large amount of salt solution with a little fresh in- 

 tact bovine serum, the addition of sensitizer in the form of heated 



