EQUILIBRIA IN ABSORPTION PROCESSES 163 



who employed for this purpose his method of study- 

 ing the conductivity. Sjoqvist stated that these substances 

 behave quite regularly as weak bases. The " mean " 

 equivalent weights of these three substances were found to 

 be about 600, 250, and 800 respectively. The egg-albumen 

 was a base about six times weaker than aspartic acid, 

 but about nine times stronger than urea. The albumose 

 (from Schuchardt) was about 1.6 times as strong a base 

 as the albumin. Sjoqvist investigated the neutralisa- 

 tion of these bases by means of different acids as hydro- 

 chloric, sulphuric, phosphoric, and lactic acid, and found 

 always a good agreement with the theoretical view. The 

 amphoteric properties of these substances have also been the 

 basis for investigations on the action of pepsin and trypsin 

 by Sjoqvist, Bayliss, and others (cf. pp. 65 and 79 above). 



A property of the antibodies, which recalls the tendency 

 of inorganic colloids to precipitate only (or chiefly) colloids 

 of the opposite electric sign, is their specificity. But 

 whereas the positive colloid ferric hydrate is attacked by 

 all the many negative colloids, the typhoid bacilli are agglu- 

 tinated only by typhoid agglutinin. Victor Henri has, in 

 association with his students, M. Malloizel and Mme. 

 Girard-Mangin, 1 carried out some experiments on agglutina- 

 tion from this point of view. He found that red blood- 

 corpuscles and typhoid bacilli are, as most substances 

 suspended in water, charged negatively, and therefore con- 

 cluded that these cells would be agglutinated by ferric 

 hydrate, as Biltz had predicted. He found that this really 



1 V. Henri et L. Malloizel : C. R. de la Soc. de BioL, 56. I. 1073 (1904) ; 

 Mme. Girard-Mangin et V. Henri : C. R. de la Soc. de Biol., 56. II. 866, 

 93L 933, 935. 936, 974 (i9<>4). 



