166 SAEKOSINE. 



solution with, very weak sulphuric acid ; treat the red 

 aqueous layer with baryum carbonate, and baryta 

 water till it turns blue, filter, shake the nitrate with 

 chloroform, and evaporate the chloroform solution in a 

 current of air. Pyocyanine will gradually deposit in 

 crystals or flakes. 



2. It is soluble in water, alcohol, and chloroform, 

 but almost insoluble in ether. Acids turn it red; 

 alkalies blue. It is decolorised by chlorine. 



3. From the mother liquor of pyocyanine, a yellow 

 substance, pyoxanthose, may be obtained. 



Saliva. 1. Extract ptyaline by the method described 

 under that body. 



2. Distil with a dilute acid (phosphoric or sulphuric) : 

 in the distillate ferric chloride will produce a red 

 colour, showing the presence of sulpha-cyanide (q.v.). 



3. Evaporate to dryness and burn. Analyse the 

 ash. It will be found to contain calcium carbonate. 



4. If the saliva be turbid, dilute it with four 

 volumes of water, and filter. The insoluble matter 

 will be tnucine. (See Mucine.) 



Sarkosine, C 3 H 7 N0 2 . 1. Boil kreatine with baryta 

 water till no more ammonia is given off, filter, add to 

 the filtrate an excess of dilute sulphuric acid, boil, and 

 again filter. Evaporate to a low bulk, mix thoroughly 

 with three or four successive small portions of cold 

 alcohol, decant the alcohol, dissolve the residue in 

 water, boil with baryum carbonate to remove sulphuric 



