PUTREFACTION PRODUCTS 



215 



solution of sodium carbonate for every liter of water previously added and 

 inoculate with some putrescent material (pancreas or feces). 1 Mix the putre- 

 faction mixture very thoroughly by shaking and insert a cork furnished with a 

 glass tube to which is attached a wash bottle containing a 3 per cent solution of 

 mercuric cyanide. 1 This device is for the purpose of collecting the methyl 

 mercaptan, a gas formed during the process of putrefaction. It also serves to 

 diminish the odor arising from the putrefying material. Place the putrefaction 

 mixture at 4OC. for two or three weeks and at the end of that time make a sepa- 

 ration of the products of putrefaction according to the following directions : 



Subject the mixture to distillation until the distillate and residue are approxi- 

 mately equal in volume. 



PART I 

 MANIPULATION OF THE DISTILLATE 



Acidify with hydrochloric acid and extract with ether. 



r ~i 



Ether Extract No. i. 



Add an equal volume of water, make alka- 

 line with potassium hydroxide, and shake 

 thoroughly. 



. 



Extract 



Residue No. i. 



Allow the ether to volatilize, 

 rate and detect ammonium 

 crystals (Fig. 60, page 216). 



Evapo- 

 chloride 



Ether Extract No. 2. 

 Evaporate spontaneously. Indote and 

 skatol remain. Try proper reactions (see 

 pages 218 and 219). 



Alkaline Solution No. i. 



Acidify with hydrochloric acid, add 

 sodium carbonate, and extract with ether. 



Ether Extract No. 3. 

 Evaporate. Detect phenol 

 (paracresol) . See page 2 19. 



Alkaline Solution No. 2. 



and cresol Acidify with hydrochloric acid, and 



extract with ether. 

 I 



Ether Extract No. 4. 

 Evaporate. Volatile fatty acids remain. 



Final Residue. 



(Discard.) 



DETAILED DIRECTIONS FOR MAKING THE SEPARATIONS 

 INDICATED IN THE SCHEME 



Preliminary Ether Extraction. This extraction may be conveniently conducted 

 in a separatory funnel. Mix the fluids for extraction in the ratio of two volumes 

 of ether to three volumes of the distillate. Shake very thoroughly for a few mo- 

 ments, then draw off the extracted fluid and add a new portion of the distillate. 

 Repeat the process until the entire distillate has been extracted. Add a small 

 amount of fresh ether at each extraction to replace that dissolved by the water in 

 the preceding extraction. 



1 Putrefying protein may be prepared by treating 10 grams of finely ground lean meat 

 with 100 c.c. of water and 2 c.c. of a saturated solution of sodium carbonate and keeping 

 the mixture at 4oC. for 24 hours. 



2 Concentrated sulphuric acid containing a small amount of isatin may be used as a 

 substitute for mercuric cyanide. When this modification is employed it is necessary to 

 use calcium chloride tubes to exclude moisture from the isatin solution. 



