102 



shows that the difficulties connected with the manufacture no longer 

 appear to be of such a severe character as formerly. The exports, 

 according to the above figures, have more than doubled in the course 

 of the last 2 years. The quality of the present season's arrivals has 

 been unimpeachable throughout. 



Pine Needle Oils. In our criticisms of Pharmacopoeias 1 ) we have 

 repeatedly pointed out that the requirements relating to the boiling 

 points of the oils are without any value unless accompanied by the 

 most precise indications as to the mode of execution of the process, 

 as the determinations are mostly wrongly conducted and result in 

 useless correspondence between manufacturers and pharmacists. Only 

 recently another such case came under our notice, in which a pine 

 needle oil supplied by us to a firm in England was being objected 

 to because its behaviour on boiling was alleged to be improper. The 

 analyst concerned had discovered that the oil contained over io°/ 

 of fractions boiling below 165 and consequently did not conform to 

 the requirements of the British Pharmacopoeia, according to which 

 not more than io°/ may pass over below 165 . A check-test made 

 in our laboratory snowed that the objection was completely ground- 

 less. The oil proved to be an altogether normal distillate, which 

 in its boiling conditions also conformed with the Biitish Pharmacopoeia, 

 inasmuch as it only began to boil at 168 . The reason for the ob- 

 jection raised was therefore to be sought entirely in the inaccurate 

 manner in which the boiling-point determination had been conducted. 

 Unfortunately such instances are very common, and it is therefore 

 earnestly to be desired that in all Pharmacopoeias the mode of carrying- 

 out boiling-point determinations should be very carefully described in 

 order to avoid such trouble. The shape and the size of the boiling 

 flask and the course of the distillation should be specified with exactness, 

 and above all, stress should be laid on the fact that the entire mercury 

 thread in the thermometer must be surrounded by the steam of the liquid. 

 Only where this is done proper results can be obtained and unfounded 

 claims avoided. 



In a fraction of Siberian pine-needle oil with b. p. 240 to 280 , 

 Wallach and Grosse 2 ) discovered a sesquiterpene C 15 H 24 which readily 

 yielded an easily crystallising hydrochloride. In order to isolate this 

 compound, the oil was boiled for about an hour w T ith concentrated 

 potash liquor and the portion boiling between 250 and 270 saturated 

 in a glacial acetic acid solution with hydrochloric acid gas. The 

 resultant tri-hydrochloride had m. p. 79 to 8o°. The hydrocarbon, 

 regenerated by heating with sodium acetate and glacial acetic acid, 



*) See Report April 1908, 128, 135; April 1909, 100. 

 2 ) Liebig's Annaien 368 (1909), 19. 



