110 EXPERIMENT STATION RECORD. [Vol.37 



The data show that the progress of decay may be readily followed by chemical 

 methods, and that even a comparative cellulose determination might serve to 

 detect incipient decay, since in the cases studied decay was accompanied by a 

 very rapid fall in cellulose content. The lignin was found to be far more 

 resistant to decay than cellulose. 



The value of a study of the process and products of decay in relation to 

 studies on the composition of the organic substances in soil is indicated. 



Tyrosinase, a mixture of two enzyms, T. Folpmeks (C/iem. Weekbl., 13 

 (1916), No. 48, pp. 1282-1289) . — The author reviews the literature on the prod- 

 ucts of tyrosinase action, and submits some experimental data which sub- 

 stantiate the contention that the reaction consists of a deaminization (by oxida- 

 tion) and then a further oxidation. 



An efficient desiccator, L. S. Pkatt {Jour. Atner. Chein. Sac, 39 (1917), No. 

 2, pp. 271-273. fig. 1). — The construction and use of the apparatus is described 

 in detail. The advantages claimed for this type of desiccator are simplicity 

 of construction and operation, rapidity of desiccation, adaptability to vacuum 

 desiccation, and adaptability to desiccation at elevated temperatures. 



A simple gas generator, R. O. Fkrnandez {Jour. Atner. Chcm. Soc, S9 

 (1917), No. 2, p. 271, fig. 1). — A simple apparatus which is indicated as yielding 

 satisfactory results is described by a diagram. 



A new direct reading refractometer with uniformly divided scale, G. W. 

 MoFFiTT (Jour. Indus, and Engin. Chcm., 9 (1917), No. S, pp. S05-309, figs. 4).— 

 The theory, construction, and manipulation of a new form of apparatus are 

 de.scritie<l in detail. 



Further studies on a numerical expression for color as given by the Ives 

 tint photometer, O. Kress and G. C. McNaughton (Jour. Indus, and Engin. 

 Chcm., 9 (1917), No. 3, pp. 282-284. fig. 1).— See al.so a previous note (E. S. R.. 

 36, p. 207). 



Determination of carbon dioxid in carbonates by diminished pressure, 

 J. B. ZiNN (Jour. Amcr. Chem. Soc, S9 (1917), No. 2, p. 270).— The author 

 recommends the use of an 8-liter aspirating bottle instead of the usual suction 

 pump as being more satisfactory and yielding excellent results in this deter- 

 minntioii. 



The Penfield test for carbon. W. G. Mixter and F. L. Haigh [Jour. Amcr. 

 Chem. Soc, 39 (1917), No. S, pp. 374, S75, figs. 5).— The application of the well- 

 known reaction for determining carbon and carbonates, which consists of heat- 

 ing a mixture of the sample with lead chroraate in a small horizontal tube, 

 near the open end of which is placed a drop of barium hydroxid solution, is 

 described. In a determination of the delicacy of the test, using a mixture of 

 silicon carbid and aluminum oxld, 0.01 mg. silicon carbld (containing 0.003 

 mg. carbon) was found to give an unquestionable reaction. It is indicated 

 that the reaction could undoubtedly be made more delicate by using a minute 

 drop of barium hydroxid solution and observing the result with a microscope. 



The volumetric determination of tin, R. L. Hallett (Jour. Soc Chem. In- 

 dus., 35 {19]6), No. 21, pp. 1087-1089). — This is a general review and discussion 

 of the procedures for the determination of tin. A bibliography of 40 references 

 to the literature cited is appended. 



On the determination of potassium as perchlorate, G. P. Baxter and M. 

 KoBAYASHi (Jour. Amcr. Chem. Soc, 39 (1917), No. 2, pp. 249-252).— From 

 solubility and analytical data reported the authors submit, as recommenda- 

 tions for the determination of potassium as perchlorate in the presence of 

 sodium, the use of absolute alcohol for washing, the use of a low temperature 

 in washing (0° C), and the use of n plntiniim-sponge crucible. The value of 

 the use of a washing liquid saturated with potassium perchlorate, as previously 



