1019] AGRICULTURAL CHEMISTRY AGROTECHNY. 31 1 



ing with urease as follows: Adsorption of Urease and Its Activity (pp. 93-9G) ; 

 Enzym Immunity (pp. 97-104) ; The Auxoaction of Amino Acids upon Urease 

 (pp. 105, 106) ; The Action of Antiseptic Substances upon Urease (pp. 107, 

 108) ; Urea Decomi»osition by Bacteria (pp. 109-11.5) ; Action of Serum upon 

 the Bacterial Urea Decomposition ; and The I'roblem of Increase of Virulence 

 of Bacteria in the Animal Body (pp. 116-122). 



The substitution of methyl alcohol and denatured alcohol for ethyl alcohol, 

 J. Pr.ESCHEK (Ztschr. Untersuch. Ndlir. v. (lemm-'^nitL, 36 {1018), No. 11-12, pp. 

 2S6, 287). 



I. Aitempis to substitute viethyl for ethyl alcohol in Ihe Gottlieb-Roese 

 method for determining fat (pp. 286, 287). — Methyl alcohol proved unreliable 

 in tlie Gottlieb-Roese test on account of the lack of a clear line of separation 

 between the ether and water layers of the mixture. 



II. 77(6 i/.se of denatured alcohol in judying tlie freshness of milk (p. 287). — 

 Alcohol denatured by the addition of pyridine bases is considered reliable for 

 this test on account of the very small amount of bases required for denatura- 

 tion. Alcohol denatured by acid is, however, considered unsuitable unless it 

 is distilled over potassium hydroxid and the first part of the distillate dis- 

 carded. 



A simple weighing burette, D. W. MacAedle {Jour. Indus, and En gin. Chem., 

 11 {1919), No. 7, p. 670, fig. 1). — The burette consists of an ordinary 100 cc. 

 Erlenmeyer flask fitted with a two-hole stopper. In one of the openings is 

 placed a glass stopcock taken from a broken burette and in the other a bent 

 glass tube drawn at the outer end to a capillary. Both stopcock and tube end 

 just below the cork and above the level of the standard solution in the flask. 

 To use the burette the cock is closed, the flask turned so that the capillary is 

 over the titrating vessel, and the solution forced into the capillary by the 

 warmth of the hand. On opening the cock the liquid will then flow freely. 

 When near the end-point the cock may be closed and the soUition forced out in 

 drops by the heat of the hand. 



The accuracy of the burette is said to be Ihnited only by the sensitiveness 

 of the end-point. 



A laboratory drying apparatus, S. Frankel {Biocheni. Ztschr., 7i {1916), 

 No. 3-Jf, pp. 170-175, figs. 3). — The apparatus, which is constructed on the 

 I)rinciples of the commercial apparatus, consists of a kettle heated with gas, 

 a condenser, and a drying cupboard which can be heated with hot water or 

 steam through a series of pipes supporting the drying tray. The vacuum is 

 obtained by means of an electric pump. 



A new condenser, S. Frankel {Biochenu Ztschr., 7Jf {1916), No. 3-4, pp. 165, 

 166, fig. 1). — The condenser described is a modified Liebig type having seven 

 small inner tubes in place of the single one of the usual condenser. 



A new form of distilling bulb, J. S. McHargue {Jour. Indus, and Engin. 

 Chem., 11 {1919), No. 7, pp. 670, 671, figs. 2).— The principal feature of the new 

 form of distilling bulb devised by the author at the Kentucky Experiment Sta- 

 tion is that tlie part within the bulb of the tube connected with the distilling 

 flask is T-shaped. The arms of the T tend to diminish the possibility of any 

 of the alkaline contents of the distilling flask being forced into the condensing 

 tube. Steam flowing out of the two arms keeps the bulb at a more uniform 

 temperature and hastens distillation. The arms of the T slope downward, and 

 the openings at the end are large enough to prevent water from being held in 

 them by back pressure. Tv.'o small holes blown in the stem of the T within 

 the bulb allow condensed water to return to the flask as soon as formed. 



The bulb is illustrated by u diagram. 



