126 THE LTSim. 



blood corpuscles is great, and leads to speedy combination between 

 the two both at high and low temperatures ; while the affinity of the 

 immune body for the addiment is slight and leads to combination 

 tardily and only at relatively high temperatures. The immune body 

 is supposed to be possessed of two haptophorous groups, one of which 

 has great chemical energy, and is that by which the immune body 

 combines with the corpuscle ; while the other haptophorous group 

 possesses less chemical energy and is that by means of which combi- 

 nation with the addiment is effected. In the first statement of his 

 theory, Ehrlich believed that the addiment is a ferment which digests 

 and dissolves bacteria and blood corpuscles. He stated : " It is 

 possible, yes, probable, that there are in the blood only a few, prob- 

 ably only a single body, which has digestive properties ; while, on 

 the other hand, there must be innumerable, different, specific immune 

 bodies, as Gruber and others have supposed. One may presume 

 therefore that in the different immune bodies only the group which 

 combines with the immunizing substance differs, while the group 

 which combines with the digestive ferment is the same in all." 



In a second series of experiments, Ehrlich and Morgenroth * im- 

 munized two goats with gradually increased quantities of defibrinated 

 sheep's blood injected subcutaneously. From these animals there 

 were obtained highly active sera. The serum of the first animal in 

 quantities of from 0.2 to 0.3 c.c. completely dissolved five c.c. of the 

 dilution of sheep's blood, while from 0.03 to 0.07 c.c. had a marked 

 effect. The serum of the second goat in quantities of from 0.15 to 

 0.2 c.c. completely dissolved five c.c. of the dilution of sheep's blood. 

 It is stated that the serum of goat II before the process of immuniz- 

 ing had a feebly solvent action on sheep's blood, inasmuch as four c.c. 

 of the serum partially dissolved five c.c. of the five per cent, dilution 

 of sheep's blood. Heating to 57° for half an hour destroyed this 

 action, also the solvent action of the same serum on rabbit's and 

 guinea-pig's blood. It was shown that the sera of both these animals 

 contained the immune body which combines with the corpuscles at 

 0°. Mixtures of these sera and sheep's blood were allowed to stand 

 for twenty-four hours at 0° and then the corpuscles were separated 

 in the centrifuge. When the sediment was shaken up with physio- 

 logical salt solution there was no hemolysis until the addiment in 

 the form of normal goat serum was added. At a temperature of 20° 

 continued for eight minutes, both components, the immune body and 

 the addiment, combined with the corpuscles and a sediment obtained 

 from this mixture and distributed in physiological salt solution and 

 kept at 37° resulted in complete hemolysis. The sera obtained from 

 these animals differed from that obtained from the goat in the first 

 series in being more intense in action and in the fact that when heated 

 to 56° for three-quarters of an hour there was scarcely any reduction 

 ^ Berliner klin. Woehensehrift, 1899, 481. 



