378 THE TYPHOID BACILLUS 



whose virulence has been increased by growing it in collodion sacs in the 

 peritoneal cavities of guinea-pigs, and to sow it in a solution of spleen peptone. 1 



Incubate at 37 C. : a week later the toxicity will be at a maximum. Then 

 either filter through porcelain, or preferably, heat to 55 C., centrifuge, and 

 decant the supernatant liquid which contains the toxin. 



(P) Properties. This toxin is more powerful than Sanarelli's and kills a 

 guinea-pig weighing 500 grams in 12-24 hours when inoculated in quantities 

 of 6 c.c. intra-peritoneally (that is about 1 c.c. per 80 grams). 



It is a very unstable product, being quickly affected by air and light, and 

 its toxic properties are diminished if it be heated to 100 C. for a few minutes. 

 It must be stored in accurately filled tubes and kept in the dark. 



3. Toxin of Bandi. The bacillus after the virulence has been raised by 

 passing it through the peritoneal cavities of a long series of guinea-pigs is 

 sown in Lceffier's broth, incubated for 4.8 hours and filtered. The filtrate 

 inoculated sub-cutaneously in quantities of 4 c.c. is sufficient to kill a guinea- 

 pig weighing 400-500 grams. 



4. Toxin of Le'pine and Lyonnet. A virulent culture in broth, 4-8 days 

 old, is sterilized at 55-60 C. for an hour. The product is toxic for dogs 

 and horses. 



5. Toxin of Rodet, Lagriffoul and Wanly. Cultures of the typhoid bacillus 

 are incubated on well aerated media for 3 days and filtered. The filtrate 

 kills guinea-pigs when inoculated intra-peritoneally in doses of 4 c.c. per 

 100 grams of body weight, and rabbits when inoculated intra-venously in 

 doses of 1 c.c. per 100 grams. 



M. and Mme.* Werner after growing the organism for 3 days in an aerated medium 

 sealed the flasks and left them for 2 days at 25 C. The filtered liquid killed guinea- 

 pigs when inoculated intra-peritoneally in quantities of c.c. per 100 grams of body 

 weight, and rabbits when inoculated intra-venously in quantities of O'l c.c. per 100 

 grams. 



6. Toxin of Moreschi. Moreschi grew the bacillus for 5 days in a special 

 broth and then filtered the culture through porcelain. The filtrate when 

 injected intra-peritoneally in doses of 0'2 c.c. killed a guinea-pig weighing 

 250 grams. 



The special broth is prepared as follows : 



Mince 1000 grams of horse meat and 1000 grams of ox's spleen, macerate for 24 

 hours at room temperature in a litre of water, boil, filter, make up to 1 litre and add 

 Witte's peptone, - 20 grams. 



Plasmon, ........ 10 



Sodium chloride, - - - . . . . . 5 



Ox blood, - - 80 



Heat the mixture to 120 C. in the autoclave for 20 minutes, neutralize, and add 

 0-15 per cent, of caustic soda. Heat again to 120 C. Filter, tube and sterilize. 



After being sub- cultured several times on this medium the bacillus grows as a 

 very thick film on the surface while the broth remains clear. When the growth 

 assumes these characteristics the culture has reached its maximum of toxicity. 



7. Toxin of Gonradi. The bacillus is grown on agar for 20 hours, scraped 

 off, mixed with a little normal saline solution and kept in the incubator at 

 37 C. for 24 hours. The emulsion is then diluted with more normal saline 

 solution and filtered through a Berkefeld bougie ; the filtrate is evaporated 



1 The medium used by Chantemesse is prepared by macerating spleen and bone marrow 

 in cold distilled water, filtering through porcelain and adding a little defibrinated human 

 blood. 



The solution of spleen peptone is obtained by digesting a pig's spleen and stomach in 

 acidulated water (vide Martin's peptone) making slightly alkaline and sterilizing. Cultures 

 are grown in a shallow layer of the medium contained in large wide-bottomed flasks. 



