420 EXPERIMENT STATION RECORD, 



alcohol there is obtained a microcrystalline aggregate with melting jtoint 1S2 

 to 135°, which is the melting i)oint of phytosterinacetatdibromid. 



Befractometric analysis of cognac, A. Frank (Ztschr. Off cut I. (Jfiem.. J.'f 

 (WOS), A'o, 10, 1)1). I8-J-J9.'i). — The author describes a method of determining the 

 alcohol and exti-act content t)f cognac from data for specific gravity and refrac- 

 tion, and gives a table showing the percentage of volume of alcohol correspond- 

 ing to these values. He concludes that the refractometer method is to be 

 recommended on the grounds of accuracy and simplicity. 



Examination of feces for nitrogen of metabolic products, A. Stutzee, E. 

 Mkrrks, and L. Seidler (Biochem. Ztschr., n (1908), No. 3-.}, pp. 310-311).— 

 According to the reported data, sheep, goat, and rabl)it feces may be preserved 

 for analysis with carbon di'^nlithid in the proportion of 1 ce. to 100 gm. feces. 

 Fairly satisfactory results are also obtained when the feces are spread out and 

 dried at ordinary room temperature. The dry material is extracted for 12 

 hours with specially prepared gastric juice and hydrochloric acid and the nitro- 

 gen determined in the undissolved residue and in the original material. The 

 difference between these values gives the nitrogen of metabolic products. 



The analysis of coal-tar creosote and cresylic acid sheep dips, R. M. Ciiapin 

 V. /S'. Dcpt. Ag)\. Bur. Aniiual Iiidii.'^. Bid. 107. pp. 7-3'), Jig. I). — This paper 

 deals with methods of determining the various constituents of dips prepared 

 from coal-tar derivatives. The commercial methods in use while rapid were 

 found untrustworthy, undecomposed rosin being distilled along with the hydro- 

 carbon and phenols even at 200° C. The scientific method requires many extrac- 

 tions and re-extractions and under certain conditions is also unreliable. In the 

 method devised by the Bureau hydrocarbons are estimated by difference, water, 

 soda, and pyridin bases, phenols, rosin acids, and other ingredients being de- 

 termined by fairly simi)le volumetric processes. Result of tests made by the 

 Bureau are reported. 



" Methods exactly parallel to the methods employed in the analysis of dips 

 may be applied to the valuation of creosote oil and cresylic acid which are to 

 be used in making dips. . . . 



" The agreement between the analysis of a dip made from analyzed materials 

 with its calculated composition indicates that it is actually possible for a manu- 

 facturer to place on the market a dip of practically unvarying composition." 



The analysis of turpentine by fractional distillation with steam, W. C. 

 Geeb {U. S. Dcpt. Agr., Forest Scrv. Circ. 152, pp. 5-29, figs. 17). — A descrip- 

 tion of important changes in methods previously employed (E. S. R., 19, p. 

 682). By means of a new form of still-head, which is described, fractionations 

 by dephlegmation are readily obtained. By using steam distillation the tem- 

 perature can also be more easily regulated. 



Results of the application of this method to 4 turpentines of different kinds 

 are shown in graphical form. The color, odor, and maximum boiling tempera- 

 ture of all fi'actions were noted and specific gravity and index of refraction 

 were determined. 



" By introducing the principle of dephlegmation the separation of the con- 

 stituents is made much more complete. . . . 



" The low temperature at which the distillation is carried out reduces the 

 danger of alteration of the sample during the analysis. 



" The distillation is similar to certain technical distilling processes which 

 have been found to give excellent results in practice and suggests the possible 

 results of applying such methods to the refining of turpentines." 



The examination of turpentine and turpentine substitutes, J. H. Coste 

 {Analyst, 33 (.1908), No. 387, pp. 2 1 9-23 -i).— The author reports a study of 



