125 



follows: The f resti meat was air-dried at a temperature of 100° C. or 

 slio-litly higher, until the fat had very hiroely separated. The fat was 

 poured oil and the dryinj^- continued until the weight beeaiue approxi- 

 mately constant, when the residues thus obtained were extracted with 

 ether to remove any remainino- fat. The extracted llesh was dried to 

 approximately constant weight and then left exposed to the air for 

 at least twenty-four hours and aoajn weiiihed. One-gram portions of 

 the air-dried sani])le thus prepared were washed Avith ether, and after 

 the ether had been allowtMl to evaporate were treated repeatedly with 

 small (juantities of water until 800 to •!(»() cul)ic centimeters had been 

 used. The nitrogen in the insolul)le residues was determined l)y the 

 Kjeldahl method. The tiltrates from the insolu])le portions of the meat 

 were placed in Kjeldahl tiasks and used for the determination of the 

 matei-ial precipitated l)y bromin (gelatinoids). The nitrogen in the 

 bromin precipitates was determined by the Kjeldahl method. The 

 percentage of nitrogen in the form of nitrogenous extractives (flesh 

 bases) was found by subtracting the sum of the tigures representing 

 insoluble nitrogen and nitrogen precipitated by bromin, from the tig- 

 ures for total nitrogen. In calculating the percentage of flesh bases, 

 tliA factor 8.12 was used, and for tiie other forms of nitrogen, the fac- 

 tor 0.25. It is evident from this outline that the results obtained are 

 not directly compara])le with those of the other investigations here 

 mentioned, since air-dried samples of flesh were used, and there is 

 nmch evidence to show that in the preparation of such samples, fresh 

 meats undoubtedly undergo various fundamental chemical changes. 



Notwithstanding the fact that so far we have not been able to learn 

 the methods used by Gautier in his investigations with meats, his 

 results are of decided interest, and the values which he reports for the 

 composition of meat are sunmiarized, with the data of the other 

 investigators referred to, in the following table: 



Table 107.— Sammar(/ of anali/f^efi of cold-water extracts of meats. 



1 Results calculated to fat-free substance. , , ,,-,.,<• , ^,^ „>. 



b The samples were air-dried before analysis, but the results have been calculated to fresh substanie. 



