Apkil 9, 1897.] 



SCIENCE. 



565 



which gave proteid reactions. After puri- 

 fication and dialysis the poison was ob- 

 tained as yellow soluble flakes which no 

 longer gave proteid reactions. It was a 

 substance in which there was no noticeable 

 phosphorus nor sulphur. It was thus 

 proved that the tetanus poison belonged 

 neither to the ptomaines before referred to, 

 nor to the proteids. The poison, while not 

 perfectly pure, was purer than any ever 

 before obtained, and was so poisonous that 

 a mouse weighing \ oz. was killed by 

 1,128.000 P^r* of a, grain, while giij- of a 

 grain should kill a man weighing 150 lbs. 



It is not diflScult to understand how if the 

 tetanus bacillus outside of the body can 

 produce such powerful poisons, it can give 

 rise in the animal organism to serious 

 troubles. The diphtheria bacillus is an- 

 other germ which forms very powerful poi- 

 sons in the solutions upon which it feeds. 

 As already mentioned, some authors, E,oux 

 and Yersin, believe that this poison also 

 belongs to the ferments like trypsin and 

 pepsin, while Brieger and Fraenkel thought 

 it was a toxalbumin. We find after the 

 germ has been removed from the culture 

 liquid by filtration, that the poison can be 

 separated by calcium phosphate or am- 

 monium sulphate, just like the tetanus poi- 

 son. In the purest condition in which it 

 has been so far obtained it fails to give the 

 proteid reaction, and -^^ of a grain will kill 

 a guinea pig. It dialyses readily. Bodies 

 of a similar kind have been obtained from 

 cholera, glanders, swine plague, tubercu- 

 losis, and anthrax cultures, while many 

 other bacteria produce soluble intensely 

 poisonous substances in artificial cultures 

 as well as inside the animal body. 



These products are all characteristic of 

 the individual organism. The conditions 

 under which the most poisonous ones are 

 formed seem to be dependent partly, we 

 may say, upon the humor of the germ and 

 also upon the food offered for its use. It 



appears, for example, in connection with 

 the diphtheria germ that, if there happens 

 to be present in the beef broth upon which 

 it is being cultivated, an undue amount of 

 glucose and an insufficient supply of alkali, 

 that, instead of producing a very active 

 poison, the substance secreted is much less 

 harmful. This is accounted for by the sup- 

 position that the glucose is decomposed into 

 acid which, in its turn, neutralizes or de- 

 composes the poison ordinai-ily produced 

 by the germ. These poisons, it was origi- 

 nally supposed, resulted from the decompo- 

 sition of the food of the germ, just as 

 soluble and assimilable albuminoids are 

 produced by the acids and ferments of the 

 animal body from the insoluble albuminoids 

 that are ingested as food. It has been 

 found, however, that in most instances the 

 poison of the germ is in solution in quan- 

 tity only after the germs themselves have 

 become partially disintegrated. In other 

 words, the active bacterial poisons seem to 

 be products of the cell and retained within 

 the cell until the latter dies and the cell 

 membrane is broken, permitting the passage 

 into the surrounding liquid of the poison. 

 What then is the true nature of these poi- 

 sons if they belong neither to the bases nor 

 to the proteids or toxalbumins ? That, un- 

 fortunately, is one of the problems to 

 which, up to the present time, chemical re- 

 search has not been able to give a definite 

 answer ; and this, because, as we have al- 

 ready noted, the poisons of these bacteria 

 are so tremendously active and conse- 

 quently produced in proportionately small 

 amount, even when a large quantity of the 

 culture media is used, that it has so far been 

 a matter almost of impossibility to separate 

 a sufficient quantity of these poisonous 

 principles to purify them perfectly for 

 chemical analysis. Perhaps this object has 

 been attained more nearly than ever before 

 by some workers in the Biochemic Labora- 

 tory in this city, who have succeeded in 



