.* 



50 PRACTICAL BACTERIOLOGY 



LXXIX. HOLZ'S METHOD, 

 POTATO WATER FOR BACILLUS TYPHI ABDOMINALIS. 



1. Wash and peel 500 grammes of potatoes, grate very fine, and 

 squeeze the juice through a linen cloth. 



& The juice is left twenty-four hours in an ice-chest before 

 filtering, or is filtered immediately through animal charcoal. 



3. Sterilize one hour in the steam sterilizer, add 10 per cent, of 

 gelatine (Eisner adds 1 per cent, of iodide of potash to the gelatine 

 before use), sterilize again one hour in the steam sterilizer, and fill 

 into test-tubes. 



4. Sterilize the tubes on each of three successive days as follows : 



First day, for 30 minutes "} 



a jj i i e j. on i. I I n the steam 

 Second day, for 15 to SO minutes > 



Third day, for 15 to 20 minutes J 



LXXX. POTATO WATER. 



FOR CULTIVATING BACILLUS TUBERCULOSIS. 



1. Grate 500 grammes of clean peeled potatoes, add 500 c.c. of 

 water, and place in an ice-chest for twelve to twenty-four hours. 



2. Decant the liquid portion and add enough distilled water to 

 make 1000 c.c. 



3. Cook one hour in the water-bath, filter, add 4 per cent, of 

 glycerine, and fill into tubes. 



4. Sterilize the tubes on each of three successive days as follows : 



First day, for 30 minutes \ 



| In the steam 



a ij * i * j. A * 



Second day, tor la to xO minutes 



Third day, for 15 to 20 minutes 



f sterilizer. 



PEPTONE MEDIA. 



LXXXI. PEPTONE WATER SOLUTION, 'KOCH.' 



Witte's peptone . . . . 2 parts. 



Sodium chloride .... 1 part. 



Distilled water . . . .100 parts. 



