218 QUANTITATIVE ANALYSIS. 



weigh the dish with its contents, remove the dry meat com- 

 pletely with a spatula, and proceed as directed in the method 

 for the "Determination of Nitrogen in the Faeces," using 0.5 

 g. of the material and 35 cc. of the fifth-normal acid. From 

 the value obtained the percentage of nitrogen in the fresh 

 meat is calculated. From this the amount in the dried meat 

 may be estimated by making use of the determination of the 

 amount of water in the fresh meat (see 1 above). 



There is no reason why the determination of the amounts 

 of water and ash may not be made with the half-dried meat 

 instead of with the fresh. Where extreme accuracy is 

 required the meat is to be dried in a vacuum over sulphuric 

 acid instead of on the water-bath (Pfliiger and Argutinsky), 

 If it is desired to make the nitrogen determination with the 

 fresh meat, weigh it off on a piece of tin-foil, fold this, place 

 it in the Kjeldahl flask, and determine the nitrogen in the 

 usual manner. 



4. Determination of Fat or Determination of the Ether 

 Extract. This is best made with the fresh meat. According 

 to the amount of fat present, weigh off accurately an aver- 

 age sample of 3 to 5 g. in a large weighing-glass, pour over it 

 about 30 cc. of absolute alcohol, stir thoroughly with a thin 

 glass rod, which is then washed off with alcohol, cork, and let 

 stand for twenty-four hours. Filter and transfer the meat 

 powder completely to the filter. Evaporate the alcoholic 

 extract to dryness and treat the residue with ether, filter, 

 wash with ether, and place the ether extract, after concen- 

 trating, in the Soxhlet extraction-flask. Place the filter con- 

 taining the meat powder in the thimble of the Soxhlet appa- 

 ratus. For further details see ' i Determination of Fat in the 

 Fa3ces," page 212. 



Pfliiger and Dormeyer recommend, instead of this method, 

 one which depends on the dissolving of the meat by digestion 

 and extraction of the solution obtained with ether (Pfliiger 's 



