124 APPLIED BACTERIOLOGY 



to determine their true character and significance. A very 

 important research has recently been carried on by Brieger 

 and Boer {Zeitschrift fur Hygiene, xxi., 268), who, work- 

 ing on filtered cultures of diphtheria and tetanus, have 

 isolated characteristic toxic bodies by a process of pre- 

 cipitation by certain metallic salts. These bodies do not 

 give the reactions of either peptone or albumose, and their 

 composition is at present quite unknown. They may be 

 entirely separate bodies, or maybe the toxicity of the toxal- 

 bumoses of Frankel, Koux, Martin, and others, may be due 

 to these bodies which have been carried down with the 

 albumoses during their precipitation, which, from the 

 chemical point of view, is quite possible. In support of 

 this theory are the facts that the organisms of diphtheria, 

 tetanus, tubercle, and cholera produce toxines in non- 

 albuminous culture liquids, and therefore the toxines may 

 be formed within the body of the organism, and not as a 

 result of the breakdown of the proteids of the culture 

 medium. 



Intracellular Poisons. — Klein,* Buchner, and others have 

 recently shown that, by intraperitoneal and by subcutaneous 

 injection of guinea-pigs with small but definite doses of the 

 protoplasm, living or dead, of various species of bacteria, 

 these animals can be rendered tolerant of further injection 

 in large amount of the protoplasm, whether the protoplasm 

 secondarily injected be derived from the same or from some 

 other species of organism. He found that the spirillum of 

 cholera and of Finkler-Prior, the bacillus of typhoid, the 

 colon bacillus, the Proteus vulgaris and the Staph, pyogenes 

 aureus, when completely separated from their metabolic 

 products, all produce one and the same disease when their 

 protoplasm is injected subcutaneously into guinea-pigs ; and 

 since they induced death under the same pathological and 

 * Local Government Board Beport, 1893-94, p. 469. 



