— 19 — 



at our works is shown by the fact that we use every month an average 

 of 20 000 kilos kernels. 



The demand for essential bitter almond oil has been normal, at un- 

 changed prices. 



We have already repeatedly referred to Rosenthaler's 1 ) researches 

 into the decomposition of amygdalin. In his last article 2 ) the author ar- 

 rives at the conclusion that the manner in which amygdalin is split up 

 under the influence of emulsin may now be regarded as entirely cleared up. 



The process is accomplished in three phases: — 



1. From amygdalin there are formed by amygdalasis mandelonitril- 

 glucoside and a-glucose. 



2. Mandelonitrilglucoside is split up by a /?-glucosidasis into d-benz- 

 aldehydecyanohydrin and /^-glucose. 



3. d-benzaldehydecyanohydrin is split up by d-d-hydroxynitrilasis into 

 benzaldehyde and hydrocyanic acid. 



Oil of Alpinia Galanga. To the note in our last Report 3 ) referring 

 to the Oil of Alpinia Galanga we are able to add the following particulars 

 from a paper which has in the meantime been published by Ultee 4 ). The 

 pale yellow oil of agreeable odour was obtained from the green rhizomes; 

 the yield being 0,04% and the constants as follow: d 2 9o 0,968, « 2 7,5o about 

 -f- 6°. The oil contains 48°/ methyl cinnamate (m. p. 34°) while its 

 cineol content (b. p. of the cineol 175 to 177°; m. p. of the iodol-compound 

 112°) is probably from 20 to 30%. A hydrocarbon with a turpentine-like 

 odour, b. p. 151 to 161° (d 25 o 0,8566; a zl0 -\- 14,90°), probably d-pinene, 

 as well as camphor (m. p. 170 to 175°) was also detected. An essential 

 oil is also obtainable from the leaves of Alpinia Galanga, but the yield 

 in this case is exceedingly slight. This oil most probably contains methyl 

 cinnamate, for upon saponification it yielded cinnamic acid. 



Oil of Andropogon Schoenanthus var. nervatus. Some time ago 

 we received from the Committee for the Economic Development of the 

 German Colonies (Kolonialwirtschaftliches Komitee) in Berlin a small par- 

 cel of a grass grown in the Soudan, of which Dr. Giessler, Curator to the 

 Botanical Institute at Leipzig, named Andropogon Schoenanthus var. nervatus, 

 as the parent plant. From this grass we distilled 1,9% of a brownish-colou- 

 red oil wich, although possessing a certain resemblance to the commer- 

 cial distillates of gingergrass, would be unable to compete with the latter 

 on account of its faint odour. The constants of the oil were as follow: 

 d l6 o 0,9405, « D +26°22', n D20O 1,49469, sap. v. 4,6, ester v. 9,3, ester v. 



*) Report November 1908, 15; April 1909, 17; October 1910, 17.. 

 *) Arch, der Pharm. 248 (1910), 534. 

 *) Report October 1910, 148. 



4 ) Mededeelingen van het Algemeen-Proefstation op Java te Salatiga. II Series, No. 45. 

 1910. From a copy kindly sent to us. 



2* 



