126 ESSENTIALS OF BACTERIOLOGY. 



by direct injection into the duodenum, after tying the gall-duct. 

 Koch alkalinizes the gastric juice with 5 c.cm. of 5 per cent, 

 sol. of sodii carbonas, and then injecting 2 grams of opium tinc- 

 ture for every 300 grams of weight into the peritoneal cavity 

 paralyzes peristalsis. The cholera culture then introduced 

 through a stomach-tube, the animals die in forty-eight hours, 

 presenting the same symptoms in the appearance of the intes- 

 tines as in cholera patients, the serous effusion containing great 

 numbers of spirilla. 



Manner of Infection in Man. Usually through the alimen- 

 tary tract, with the food or drink, the intestinal discharges of 

 cholera patients having found entrance into the source of drink- 

 ing water. Soiled clothes to fingers, fingers to the mouth, etc. ; 

 torpid catarrhal affection of the digestive tract predisposing. 

 The microbe is not found in the blood or any organ other than 

 the intestines, the tissue of the small intestines. It is also 

 found in the vomit and the intestinal contents. 



FIG. 65. 



N J^~* ** 



-& 



Comma bacillus in mucus, from a case of Asiatic cholera. 



Products. " Cholera red." When chemically pure nitric or 

 sulphuric acid is added to nutrient peptone cultures of the 



