1909.] 



PUBLIC DOCUMENT — No. 31. 



115 



extracted at least part of the oil ou which they worked with 

 ether. A more accurate determination, by means of an ordinary 

 picnometer, proved unsatisfactory at the low temj^erature de- 

 sired because of the viscid nature of the material. 



The specific viscosity was reported by F. W. Farrell * as 

 8.43, using a Boverton-Redwood viscosimeter. This indicates 

 the rate of flow at 70° F., as compared with a like volume of 

 water at the same temperature. 



The refractive index NTd and mean dispersion Np — Nc 

 were determined at several temperatures by an Abbe refrac- 

 tometer with a water jacket. 



The Valenta test, or turbidity point of equal volumes of oil 

 and glacial acetic acid, was 60° C. This test is based on solu- 

 bility. 



(h) Chemical Tests. 



In the chemical examination of the oil the usual methods, 

 with only slight modifications, were followed, unless otherwise 

 stated, and they are too well known to need description. 



1 Of the Emerson Lnboratory, Springlield, Mass. 



2 Calculated from an acidity of 2.28 per cent, as oleic acid. 



3 Excluded fi'om the average. 



* Vyestnik Obshch. Hig., Sudeb. i. Prakt. Med. 5 (1905), pp. 690-693; Abs. Exp. Sta. 

 Rec, 18, p. 8.58. 

 6 Average. 



