164 PUS. 



5. Heat with soda lime in a tube : ammonia will be 

 evolved, showing presence of nitrogen. 



6. Fuse with caustic potash, dissolve in water and 

 add a drop of lead acetate. A black precipitate will 

 form, showing presence of sulphur. 



Pus. 1. Examine under^ microscope : pus corpuscles, 

 identical with the white corpuscles of the blood, will 

 be noticed. Observe appearance and reaction with 

 litmus paper. 



2. Exhaust the pus with twice its volume of boiling 

 90% alcohol, containing a little hydrochloric acid, 

 evaporate to one third, mix with three or four times 

 its bulk of ether, shake well, and decant or fill the 

 liquid. Examine the solution and the insoluble residue 

 by the methods described under fats ; cerebric, oleic, 

 and palmitic acids and cholesterine will be found. 



3. Dilute pus with three volumes of water containing 

 a little sodium chloride, and by nitration and decanta- 

 tion separate the corpuscles from the serum. 



4. Heat the serum : a precipitate of albumen will be 

 formed. Filter : test a portion of the nitrate for sugar 

 by the copper test. Evaporate another portion to a 

 low bulk and add nitric acid ; a crystalline precipitate 

 of urea nitrate will indicate urea. In another portion 

 test for leucine (q-v.). 



5. Digest the corpuscles with a 10% solution of 

 sodium chloride, filter or decant, and mix the solution 

 with a large quantity of distilled water. A flaky 

 precipitate will form of a substance allied to myosine. 

 The portion of the corpuscles insoluble in sodium 



