is somewhat influenced by the temperature; a solution of 20 per cent. camphor, 
as frequently produced by action of bacteria. ‘The fret distils the aicowol | 
p. 61 of this Report. 
Estimation of camphor in solution with fatty oils. — The process ‘adopte ys ; 
German Pharmacopeeia for the estimation of camphor in Olewm camphore wm (th oil 
is heated on a water bath for one hour and must lose about one-tenth of it ‘V 
is incorrect; in addition, the time given is too short. For this reason, O. von Frie d 
Suggests. measuring the optical rotation, a method which is applicable whe : 
natural camphor of high rotatory power is used. He investigated | camphor ‘ coils 
composed of olive, colza, or sesame oils with increasing amounts of esac: 
from 2 to 25 per cent., and found e.g. for 
1. camphor in olive oil . . 10 percent.) 10.220; 20, per cent.: aaah 42° ta 
2. camphor in colza oil . . 10 percent.: + 9.779; 20 percent.: + 18. 86°; 2 ; 
3. camphor in sesame oil . 10 percent.: + 11.569; 20 percent.: eee 55°. . 
With olive oil, the percentage may He calculated according to the equatio 
p = 1.958 < <, with colza oil: p= 1.963 >< — ~ +041, with sesame oil: DS 224 5 4 
where « = angle of rotation, / = length of steel tube in decimeters. ‘The reading : 
instance, showing at 14° -+ 20.285°, rotated at 20°: 20.395, and at a 20 480. 
For the purpose of identifying phenols, E. E. Reid?) makes use ‘of pntiaae Ts 
bromide, which reacts cleanly and quantitatively with alkali phenolates. The ethe : 
resulting crystallize easily from dilute alcohol, melt sharply, and are suitable f 
identification purposes. The following ethers were prepared by the author: — t 
p-nitrobenzyl ethers of phenol (m.p. 91°), o-cresol (m. p. 89.7%), m-cresol (m. p. 51' 
p-cresol (m.p. 88°), thymol (m.p. 855°), eugenol (m.p. 53. 6°), and vanillin (m.p. 124. 
As to the identification of phenol (carbolic acid) and of methyl Phydroxybe 
in oil of wintergreen, see p. 64. os 
Concerning the estimation of thymol, wide p. 70 of this Shia 
Estimation of butyric acid and of other fatty actds. — Many years Fee _Ducta 
neutralized liquid, then adds a solution of tartaric acid and distils the acids 
fractionation in this manner that from 110 ce. of the eh the -distillats He 
lime water) manifests itself by the anes in colour of the indicator “dee 
The first fractions contain the more volatile acids, the later face the 
1) Svensk Farm. Tidskr. 1918, No. 12, p. 197; Apoth. Zig. 33 1918), 27. ee 
(1918), 450. — %) Journ. Amer. chem. Soc. 89 (1917), 304; Zeitschr. fe Ra ek Che Ri. 
8) Ann. Inst. Pasteur 9 (1895), 265; Chem. Zentralbl. 1895, A! Ys 1086. ape ir 
