198 SPECIAL MEDIA 



Beyrinck's Solution. II. (For growth of Azobacter.} 

 Proceed as in preparing solution No. i, substituting mannite for 

 dextrose in step 5. 



Winogradsky's Solution (for Nitric Organisms) . 



1. Weigh out and mix. 



Potassium phosphate i . o gramme 



Magnesium sulphate 0.5 gramme 



Calcium chloride o.oi gramme 



Sodium chloride 2.0 grammes 



and dissolve in 



Distilled water 1000 c.c. 



2. Fill into flasks, in quantities of 20 c.c. and add to each a 

 small quantity of freshly washed magnesium carbonate. 



3. Sterilise in the steamer at 100 C. for twenty minutes on 

 each of three consecutive days. 



4. Add to each flask containing 20 c.c. solution, 2 c.c. of a 

 sterile 2 per cent, solution of ammonium sulphate. 



5. Incubate at 37 C. for forty-eight hours and eliminate any 

 contaminated culture flasks. Store the remainder for future use. 



Winogradsky's Solution (for Nitrous Organisms). 



1. Weigh out and mix 



Ammonium sulphate i gramme 



Potassium sulphate i gramme 



and dissolve in 



"Distilled water 1000 c.c. 



2. Add 5 to 10 grammes basic magnesium carbonate, previously 

 sterilised by boiling. 



3. Fill into flasks and sterilise, etc., as for previous solution. 



Silicate Jelly (Winogradsky). 



1. Weigh out and mix 



Ammonium sulphate 0.40 gramme 



Magnesium sulphate 0-05 gramme 



Calcium chloride o.oi gramme 



and dissolve in 



Distilled water 50 c.c. 



Label Solution A. 



2. Weigh out and mix 



Potassium phosphate o.io gramme 



Sodium carbonate 0.60 gramme 



and dissolve in 



Distilled water 50 c.c. 



Label Solution B. 



