Commercial and scientific notes on essential oils. 43 



Sheih Oil. — By the name of Sheik or CJiieh the Arabs designate plants of strong 

 odour growing in North Africa, the essential oils of which have been investigated by 

 E. Grimal 1 ), P. Jeancard and C. Satie 2 ) and by Schimmel $ Co. 3 ). Grimal states that 

 he obtained the oil from the Artemisia herba-alba, Asso, which is common in Algiers; 

 Jeancard and Satie do not give any further information as to their plant which also 

 came from Algiers; Schimmel $ Co. had experimented with the Artemisia herba-alba 

 var. densiflora, Boiss. 



Roure-Bertrand Fils 4 ) have recently further investigated a sheih oil from Algiers. 

 In the course of this investigation E. G. and A. Camus found that Artemisia herba-alba 

 occurs in North Africa in four different varieties: — (1) var. genuina, Battand et Trab., 

 widely distributed; (2) var. jpatula, Battand et Trab., also commonly found; (3) var. 

 oranensis. Debeaux Assoc, (fr. Congres d'Oran, Oran); (4) var. densiflora, Boissier, Sahara. 



The oil examined by Roure-Bertrand Fils came from Artemisia herba-alba. Asso 

 var. genuina. Battand et Trab. Since this plant, sometimes also called white mugwort, 

 grows in ample quantities in Algiers, but only in the high mountains, it was not quite 

 easy to obtain the necessary material. The same authenticated sample of this scheih 

 oil was studied before and after the war. It was then ascertained that the oil had 

 strongly changed during the six years of storage,, and that resin acids had been formed 

 in particular at the expense of the free alcohols. Especially noteworthy was, in addition 

 to the large increase in the acid value (from 3.5 to 29.87) and to the diminished 

 solubility in alcohol, the change in the optical rotation (from +2°6' to — 13°24'). 

 The constants of the two samples were the following: — 



Date of examination. 1914. 1920. 



i 



colour light brown brown 



d 15 o : . . . 0.9432 0.9534 



D17° 



-f2°6' — 13°24' 



solubility in 70 per cent, alcohol. ... in 1.4 vol. (turbidity) almost insoluble 



acid v 3.5 29.87 



ester v 53.9 53.2 



ester v. after acetyl 147 84 



total alcohol (calculated as Ci H 18 O) . . 45.44 per cent. 24.65 per cent, 



free alcohol 30.64 per cent. 10.01 percent. 



After a second steam distillation the stored oil yielded 72 per cent, of an almost 

 colourless liquid, the odour of which suggested cineole, menthol and camphor; the 

 properties were: — d 15o 0.9365; « D i 5 o — 19°; n D15 o 1.4710; soluble in 15 vol. of 60 percent, 

 alcohol, in 1 vol. of 70 per cent, alcohol, easily soluble in 80 per cent, alcohol ; acid v. 7.47, 

 ester v. 41,06, sap. v. 48.53; ester v. after acetyl. 41.06; total alcohol (calculated as 

 CioHi 8 0) 1 1 .29 per cent.; free alcohol per cent. The distillation residue (about 25 per cent. 

 of the original oil) was a sluggish liquid, deep red brown, of balsamic odour and the 

 following constants: — d 16 o 0.9685, acid v. 93.33, ester v. 82.13, sap. v. 175.46; ester v. 

 after acetyl. 163; total alcohol (as Ci H 18 O) 46.26 per cent.; free alcohol 23.68 per cent. 

 The new distillate was distilled in vacuo sand gave the fractions: — 60 to 105° (25 mm.) 

 7.0 g., d^0.9065, « D160 — 27°36'; 105 to 110° (25mm.) 9 g., dJgO.9469, « D16 o — 32°4'; 

 110 to 120° (25 mm.) 6 g., d^ 0.9531, « D16 o — 39°; 120 to 125° (14 mm.) 3 g., dJgO.9563, 

 fouo— 31°12'; 125 to 130° (14 mm.), 1.5 g., « D i 6 o — 7°40'; residue 2 g. 



2 ) Cf. Gildemeister and Hoffmann, The Volatile Oils, 2 nd ed., vol. Ill, p. 648. — 2 ) lUdem, p. 668. — 

 p. 649. — *) Bull. Jionre-Bertrawl Fils, avril 1920, 18. 



