- 28 — 



below 1,4960 (25°) as suspect, an assumption which seems to be very 

 much in need of corroboration, and which, for instance, is not in accord 

 with the statements by E. F. Harrison and P. A. W. Self set forth below. 



Harrison and Self 1 ) have also investigated asafoetida and have pre- 

 sented the results of their observations in a paper read before the Pharma- 

 ceutical Society of Great Britain. They examined 15 different samples of 

 asafoetida, drawn from large parcels. They determined the percentages 

 of loss on drying in a water-oven, the percentage of resin, of mineral 

 constituents (ash) and of essential oil. The latter they examined more 

 closely. With the exception of one sample, which came from Bombay, 

 all the samples had been taken from parcels imported from the Persian 

 Gulf. We will here only refer to that part of the interesting paper which 

 deals with the examination of the essential oil. 



Harrison and Self determined the oil-content of each sample by steam- 

 distillation. By this method they obtained from 5,8 to 17,1% oil, that is 

 to say, in part considerably higher yields than had been observed previ- 

 ously 2 ). Umney and Bunker 3 ) alone have obtained approximately equal 

 values (from 12 to 16°/o) but these were obtained by a different method 

 of determination. 



The characters of the oils obtained from Persian asafoetida fell within 

 the following limits of value: di 6(5 o 0,915 to 0,981, « D + 9°39' to — 17°3\ 

 n D2 oo 1,4942 to 1,5207. Sulphur-content 17,5 to 29,2%. A high sulphur- 

 content was mostly found in combination with high sp. gr., high refraction, 

 and dextrorotation. 



The gum-resin from Bombay yielded 7,5% oil of somewhat different 

 constants (di 5 ,5o 0,993; « D — 35° 55'; n D20 o 1,5250; 37,8% sulphur) and, ac- 

 cording to Harrison and Self, is probably less valuable than the other 

 samples. 



The experience of Umney and Bunker (loc. cit.) that oil from asafoetida 

 in tears contains a higher proportion of sulphur than oil from asafoetida 

 in mass has not been confirmed by Harrison and Self; on the contrary, 

 their samples showed the same average sulphur-content, whether mass or 

 tears. They believe that Umney and Bunker have operated under serious 

 loss of sulphur, volatile sulphur-compounds having escaped in the course 

 of their examination. They themselves have tried to determine the sulphur- 

 content by different methods and have come to the conclusion that the 

 following method is that which yields the best results: — 



About 0,5 g. of the oil is weighed into a 150 cc. flask, connected bv, 

 a ground joint to the tube of a vertical condenser; 5 cc. of water, is added 

 through the tube, followed by 5 cc. of nitric acid (di 5 ,5o 1 ,42). The flask 



t 



x ) Pharmaceutical Journ. 88 (1912), 205. 



2 ) Gildemeister and Hoffmann (loc. cit.) give from 3 to 6,7 °/o 



3 ) Comp. Report October 1910, 20. 



