808 EXPEEIMENT STATIOX EECOKD. 



" In conducting this hydrolysis, care was taken to keep account of the 

 undetermined substance, in order to get a clearer idea of its approximate 

 amount, and if possible to locate the large loss indicated by the low summation. 



" The substances making up the total are stated as the free amino-acids, 

 and. in addition, a small amount of ammonia. The amino-acids are doubtless 

 united in the protein molecule with the elimination of a molecule of water for 

 each molecule of acid, and it is not improbable that the ammonia is combined 

 with one carboxyl group of the dibasic acids." 



According to the authors' calculations, at least 30 per cent of the vignin is 

 not accounted for after hydrolysis. " The substance obtained from the un- 

 esterified and ether insoluble part of the products of hydx'olysis, which was 

 examined for oxyprolin, weighed only 62.6 gm.. equal to 12.26 per cent of the 

 vignin. Of this, 7.58 per cent is included in the 20 i^er cent of unesterified 

 amino acids, leaving only 4.68 per cent for unknown substances. It would 

 seem from these figures that the losses which are practically imavoidable in 

 carrying out these analyses may have a larger share in explaining the de- 

 ficiency than has been heretofore supposed. 



" It does not, however, seem probable that this apparently large deficiency 

 consists to any considerable extent of products of decomposition already known. 

 The amount of the substances that are determined directly, probably nearly 

 represents the quantity in which they are produced by hydrolysis, for the de- 

 terminations of glutaminic acid can be controlled to a certain extent by the 

 results obtained by the ester method, and those of arginin, histidin, and lysin 

 are, as will later be shown, accurately controlled by the nitrogen precipitated 

 by phosphotungstic acid. The ammonia determinations are accurate. 



" The known protein decomposition products which were not determined in 

 this analysis can not be relied on to account for this difference." 



An improvement in the technique in the hydrolysis of protein. The em- 

 ployment of hydrofluoric acid and its advantages, L. Hugounenq and 

 A. Morel (Jour. I'harm. ct Chim., 6. ser., 28 (J008), No. 11, pp. 4S6-.'t93).— 

 According to the authors, hydrofluoric acid possesses a number of advantages 

 as a hydrolyzing agent. A smaller quantity of humic substance is produced 

 than is the case with sulphuric or hydrochloric acid and the cleavage of protein 

 to ammonia is smaller. 



Concerning' the identification of sugars, J. J. Blanksma and W. A. Van 

 Ekenstein iChem. WcekbL, 5 (1908). No. 42, pp. 77'7'-7'8i). — A summary and 

 discussion of methods for the identification of sugars of different sorts. 



Identification of 5-fructose in the presence of other natural sugars, J. 

 Pieraerts {Bui. Soc. Chim. France, ^. ser., 3 (1908), No. 18-19, pp. 966-98^).— A 

 critical study of methods. 



The rapid determination of sugar in scum, H. Pellet {Betterave, 18 (1908), 

 No. Jf65, pp. .'f02~j!fOJi). — The author describes a method which he has found sat- 

 isfactory for use in beet-sugar factories. 



The Fieh reaction for invert sugar in honey, Drawe (Ztschr. Offentl. Chem., 

 14 (1908), No. 18, p. 352). — A controversial article. 



Concerning the biological method for the examination of imported meat, 

 M. MtJLLER (Ztschr. Fleisch u. Milchhyg., 19 (1908), No. 1, pp. 9-i2 ) .—According 

 to the author, the biological method may be satisfactorily used for the identifi- 

 cation of dried intestines from different sorts of animals. 



Sulphured fruit, H. Luhrig (Phnrm. Centralhallc. 49 (1908), pp. 831-8.54; abs. 

 in Chem. CentbL, 1908, II, No. 19. pp. 1622. 1623).— The investigations carried 

 on by the author indicate that the sulphur dioxid content of sulphured fruit 

 varies so greatly in different portions that a large quantity should be available 

 for inspection work rather than a small sample. 



