Chemical Preparations and Drugs. 87 



The Pharmacopoeia prescribes the following method of standardization for this oil: — 

 if one shakes 5 ccm. of oil of thyme thoroughly with a mixture of 10 ccm. of caustic 

 soda solution and 20 ccm. of water and than lets it stand till the layer of caustic soda 

 has become clear again, the volume of the oil-layer swimming on its surface must 

 not exceed 4 ccm. at the utmost. 



Frerichs adds the following remarks:— that the determination, if executed with 

 a graduated measuring cylinder of 100 ccm. capacity, is always very inexact. Further, 

 that the little measuring flask used for the standardization of oil of cinnamon is very 

 suitable for this purpose, if the neck is graduated for at least a space of 4 ccm. By 

 filling up with the same mixture of caustic soda and water, the undissolved oil can 

 be brought up to the upper mark. The aqueous liquid only becomes clear after a 

 very long time. The oil itself remains turbid even for a much longer period. However, 

 it is sufficient to let the little flask stand just long enough for the oil to separate from 

 the aqueous liquid. 



Chemical Preparations and Drugs. 



Almond Oil, expressed. The present lack of fatty almond oil and of other oils 

 and fats has also drawn general attention to the utilization of plum stones 1 ). Hence 

 F. Darvas 2 ) publishes that he produced a first-rate table oil from plum stones. For 

 trial purposes he freed 5 kg. of plum stones from their outside hard shells and thereby 

 obtained 1 kg. of kernels, from which he produced 200 g. of fatty oil. He submitted 

 the expressed residue to dry steam distillation and collected the distillate in 20 per cent, 

 alcohol, whereby he obtained 670 g. of a solution of 1.3 to 1.4 percent, benzaldehyde 

 cyanhydrine. The residue consisted of a press-cake, poorer in oil, but richer in albumen, 

 weighing about 800 g. On repeating his experiments the results hardly varied at all. 



The fatty plum oil (Oleum prunorum) had, after necessarily being purified, a golden- 

 yellow colour, was transparent, totally odourless, had a pleasent mild taste and a 

 congelation point of about —17°. Constants, d 0.9169 to 0.918; acid value 1.8 to 2.1; 

 iodine value, 97.5 to 100.6. One can say in a general manner that plum oil ranks between 

 almond oil and sesame oil; it is equally suitable as a table oil and for medical purposes. 



The Aqua prunorum prepared by Darvas according to the prescription of the 

 Hungarian Pharmacopoeia for the preparation of Aqua amygdalarum amararum was a 

 solution of from 1.3 to 1.4 per cent, benzaldehyde cyanhydrine. The distillate obtained 

 was diluted to a content of V 10 P© r cent. The Aqua prunorum, thus prepared, is 

 colourless and quite transparent; the smell is exactly like a good quality of bitter 

 almond water. The residue of the preparation of plum oil and of plum water can be 

 used for cosmetic purposes (instead of almond-powder) and also, owing to its richness 

 in albuminous substances, as a particularly nourishing food for animals. 



Anethole. According to R. Meldrum 3 ), anethole is a highly suitable substance for 

 determining the melting and congelation point, because it crystallizes easily and melts 

 already at ordinary room-temperature. He made his experiments in a tube of about 



x ) Comp. Report October 1916, 67. — 2 ) Zeitschr. d. aUg. osterr. Apoth. Yer. 54 (1916), 419. — 3 ) Chem. 

 News 112 (1915), 259. — Comp. ibidem 111 (1915), 95. 



