138 



ESSENTIALS OF BACTERIOLOGY 



congested spleen. Metastatic abscesses form in various parts 

 of the body, and here likewise the organisms abound. They 

 occur in the feces only in small numbers, more commonly in 

 the urine. The urine may contain active bacilli for weeks 

 after recovery from the fever. 



Typhoid Bacilli in Water. Although all evidence shows 

 that the water-supply is a frequent source of infection, very 

 few persons have ever isolated the typhoid bacillus from such 



Fig. 60. Bacillus typhosus. Impression preparation from gelatin 

 plate. Fuchsin (Xiooo) (Hicks). 



an infected source. The earlier reports show that no account 

 was taken of Bacillus coli, which is usually present in pol- 

 luted waters. (See Water Analysis.) 



Persistence in Water. Franckland kept bacilli alive in 

 water, sterilized by heat, seventy-five days; in filtered water 

 at 19 C., five days; at 6 C., twelve days. In ordinary water 

 they are likely to be destroyed in a short time by the over- 

 growth of other bacteria. Under ordinary conditions they 

 do not multiply, but decrease steadily in numbers. In soil 



