1913] Jacob Shulansky and William J. Gies 47 



cated by Moritz several years ago, but it appears to have failed to 

 meet with much approval : Arch. f. klin. Med., Ixxxiii, p. 567, 1905." 

 This quotation virtually begs the question. Results of experiments 

 shozving " that the carbonate is the safer reagent," instead of com- 

 ment on the failure of Moritz's Suggestion "to meet with much 

 approval," would have been convincing. With all due respect for 

 Folin's opinion, we must await a demonstration of the superiority of 

 sodium carbonate over sodium hydroxid in the aeration process, 

 before we can agree with Polin that the modified method is not de- 

 cidedly better than the old. 



Application of the modified method to beef. In October 

 19 IG, soon after Dr. Steel's departure from this laboratory to ac- 

 cept a professorshipat the University of Missouri, we began a series 

 of experiments to determine the efficiency of the NaOH-NaCl 

 method when applied to the determination of the ammonium nitro- 

 gen in beef. It appeared probable that the protein in meat would 

 yield, under such conditions, particularly large proportions of am- 

 monia as a result of hydrolysis by the caustic alkali ; and we desired 

 to ascertain the degree of deficiency, if any, of the method from 

 this Standpoint. 



Most of the data recorded in this paper were obtained by the 

 junior author in iqig-'ii, but verifications were occasionally con- 

 ducted by the senior author during that year and the ensuing one. 

 Publication of the results has been purposely delayed in order that 

 the data might accompany the succeeding paper by Dr. Smith,^ 

 whose work was begun in September, 191 1. 



2. Comparative efficiency of the NaaCOg-NaCl and NaOH- 

 NaCl aeration methods for the determination of ammonium( 

 nitrogen. I. Fresh beef. In our direct comparison of the effi- 

 ciency of the two aeration methods when applied to meat, we con- 

 sidered it possible that (A) the protein of meat might yield consid- 

 erable ammonia by hydrolysis, and (B) that some of this ammonia 

 might combine in part with magnesium and phosphate in the meat to 

 produce ammonio-magnesium Phosphate ;*5 (C) that the ammonium 



5 Smith : Biochemical Bulletin, 1913, iii, p. 54. 



« Crystals of ammonio-magnesium phosphate form promptly in muscle fibers 

 exposed to ammonia fumes or immersed in ammoniacal Solutions. 



