68 Chapter IV 



When we inject milk, blood serum, or white of egg, that is to say, 

 materials very rich in albuminoid substances, under the skin or into 

 the peritoneal cavity of laboratory animals, we find that after a time 

 they disappear. At the same time they give rise to modifications of 

 the organism which indicate that these injected substances have there 

 undergone profound changes. 



After injecting eel's serum into rabbits, Th. Tchistovitch 1 found 

 a substance in the blood of the injected animals which gave a 

 precipitate with eel's serum. Shortly afterwards Bordet 58 observed 

 that the blood of animals into which he had injected cow's milk 

 acquired a new property : it gave a precipitate with this milk, a con- 

 dition never observed in the serum of untreated animals. 



The injection of white of egg into rabbits, carried out by Myers 3 

 and Uhlenhuth 4 , brought about the same changes in the blood serum. 

 The researches of the latter of these two observers have for our 

 present purpose a special interest. He demonstrated first that the in- 

 jection of white of egg into the peritoneal cavity of rabbits was followed 

 by the appearance in the blood serum of these animals of a substance 

 which precipitates egg albumen in vitro. Uhlenhuth then obtained 

 this same acquired property of the blood in rabbits which had been 

 made to swallow a considerable quantity of the white of hens' eggs. 

 Twenty-four days after the commencement of this regimen the serum 

 of the rabbits precipitated white of egg in the test-tube. This example 

 affords a marked analogy between the results of digestion in the 

 alimentary canal and those of resorption into the tissues. Uhlenhuth 

 points out, indeed, that his rabbits which received the injections of 

 white of egg into the peritoneal cavity flourished under this treatment. 



A certain number of similar examples are now recognised. They 

 all indicate that various nutritive substances, when introduced into 

 the peritoneal cavity or under the skin of animals, are retained there 

 for a longer or shorter time and are subjected to certain modifying 

 influences on the part of the organism. The proof that these 

 [74] substances are not eliminated intact by the kidneys has been 

 furnished by a large number of experiments. Recently Lindemann 5 

 and NeTedieff 6 , working in my laboratory, have established the fact 



1 Ann. de Vlnst. Pasteur, Paris, 1899, t. xm, p. 406. 



2 Ann. de VInst. Pasteur, Paris, 1899, t. xin, p. 225. 



3 CentralU.f. Bakteriol u. Parasitenk., Jena, 1900, I te Abt, Bd. xxvin, 8. 237. 



4 Deutsche tried. Wchmchr., Leipzig, 1900, S. 734. 

 6 Ann. de llnst. Pasteur, Paris, 1900, t. xiv, p. 49. 

 6 Ann. de VInst. Pasteur, Paris, 1901, t. xv, p. 17. 



