xn,B.6 Schobl: Survey of Certain Chemicals .219 



were placed in the sixth group. Magnesium peroxide, potassium 

 iodide, potassium permanganate, calomel, mercury salicylate, an- 

 timony tartrate, antimony trioxide, arsenic trioxide, sodium ca- 

 codylate, atoxyl, 606 Ehrlich. 



The seventh group comprises a few anilin dyes. It is known of 

 some of these chemicals that they act in vitro as strong and 

 selective antiseptics. The following dyes were tested : Methylene 

 blue, gentian violet, brilliant green, fuchsin, trypan red and blue, 

 scarlet red, chrysoidin, vesuvin, victoria blue, and crystal violet. 



Judging the effect of drug treatment by the results of these 

 experiments, one can see that none of the drugs tested showed 

 such prompt effect as to bring complete sterilization of the ani- 

 mal's body organism in a short time in every case. 



Nevertheless there are certain indications evident of the pos- 

 sibility of shortening the duration of the state of cholera carrier. 

 The effect of drug treatment in our experiments appears to be 

 of three degrees. 



First degree. — The absence of cholera vibrios on the direct 

 plates made from the intestine, indicating diminution of cholera 

 vibrios in the intestinal tract. Findings of this type are con- 

 sidered of little importance, since physiologic conditions un- 

 doubtedly influence the variation in numbers of cholera vibrios 

 in the intestine. Nevertheless, compared with the findings in 

 untreated controls, the absence of cholera colonies on direct plates 

 can be considered as an effect of drug treatment, and drugs 

 effecting such findings deserve further attention. 



Second degree. — Absence of cholera vibrios on direct plates as 

 well as in peptone cultures both made from the intestine, in- 

 dicating absence of cholera vibrios from the intestine at that 

 time. Drugs showing this effect may reasonably be considered 

 intestinal antiseptics of value, in as much as they bring about 

 a disinfection of the intestine even if only temporarily. 



Third degree. — Absence of cholera on all direct plates and in 

 all peptone cultures, including those made from bile and from 

 the gall bladder. Considering the ease with which cholera vi- 

 brios can be detected with the aid of a selective medium and par- 

 ticularly by employing the peptone enrichment process, one is 

 bound to consider these findings as sufficient evidence of complete 

 absence of cholera vibrios from the body organism. 



In this group (Table I) only benzene showed a slight effect in 

 as much as one out of three guinea pigs after ten days' treat- 

 ment harbored so few cholera vibrios in the intestine that none 

 grew on direct plates. Cholera vibrios, however, were detected 

 by the enrichment process. 



