82 TOXINES AND ANTITOXINES. 



dieted by the undoubted changes that can be detected in the 

 poison itself, to attempt, like DANYSZ,* to attribute every altera- 

 tion in the action to changes in the surrounding media. The 

 other external characteristics are quite analogous to those 

 belonging to all enzymes. 



Diffusion through parchment can be plainly perceived. Thus, 

 when 5 c.c. of the poisonous bouillon were diffused into 12 c.c. of 

 water, there passed through, on the average, in twenty-four hours 

 a lethal dose for guinea-pigs (Roux and YERSIN). On the other 

 hand, it does not diffuse through membranes formed from the 

 organs of animals e.g., the oesophagus, large intestine, the 

 gall bladder, and the small intestine (CnASSiN and Moussu 2 ). 

 Nor does it pass through collodion (RoDET and GUECHOFP 3 ). 



It is completely insoluble in pure alcohol, which, however, 

 slowly destroys it (WASSERMANN and PROSKAUER, loc. cit.), as 

 also does acetone and ether (BRIEGER and BOER, loc. cit.). It is 

 likewise destroyed by the digestive ferments in the stomach and 

 intestine (PALTSCHiKOWSKi 4 ). 



Like the enzymes, it is carried down from its solutions by 

 falling precipitates. On fractional precipitation with calcium 

 chloride the resulting calcium phosphate precipitate simul- 

 taneously removes a large proportion of the toxine, the second 

 precipitate being the most poisonous. The precipitation, how- 

 ever, is never quite complete, still less so in the case of aluminium 

 phosphate. In particular, the characteristic poisons that pro- 

 duce the secondary paralysis remain for the most part in solution. 

 This calcium phosphate precipitate can be heated to 70 C. 

 without injury, and is not perceptibly damaged by being kept 

 for twenty minutes at 100 C. When subcutaneously injected it 

 slowly parts with its poison, besides producing inflammatory 

 processes (separation of fibrin, false membranes), so that it 

 appears to act exactly like the living bacilli. It is also pre- 

 cipitated by nucleo-histone and nucleic acid (FREUND and 

 GROSZ 5 ). Toxines almost free from ash can be obtained by 

 dialysing the aqueous extract of this precipitate, or by precipita- 

 tion with alcohol. 



1 Danysz, "Constitution des toxines," Ann. Past., xiii., 581, 1899. 



2 Chassin and Moussu, "Influence de la dialyse, &c.," Soc. Biol., lii., 

 694, 1900. 



3 Rodet and Gue'choff, Soc. Biol, lii., 965, 1900. 



4 Paltschikowski, " Ueb. d. Veranderungen der diphtheritischen Toxine 

 in dem Nahrungswegen," Abst. Centralbl. f. Bakt., xxv., 1899. See also 

 the General Part. 



5 Freund and Grosz, " Ueb. d. Bez. zw. Gerinnung u. d. Wirkg. d. Anti- 

 toxine," Centralbl. f. inn. Med., 1895, 613, 637, 



