OLEUM NEROLI. 127 



solution of quinine. In oil of Xeroli the phenomenon may be shown 

 most distinctly by pouring a little spirit of wine on to the surface of 

 the essential oil, and causing the liquid to gently undulate. The oil is 

 but turbidly miscible with bisulphide of carbon. It assumes a very 

 pure, intense, and permanent crimson hue if shaken with a saturated 

 solution of bisulphide of sodium. Examined in a column of 100 mm. 

 we observed the oii to deviate the ray of polarized light 6° to the 

 right. 



Subjected to distillation, the larger part of the oil passes over at 

 185°-195° C. ; we found this portion to be colourless, yet to display in a 

 marked manner the violet fluorescence and also to retain the odour of 

 the original oil. The portion remaining in the retort was mixed with 

 about the same volume of alcohol (90 per cent.) and some drops of 

 water added, yet not sufficient to occasion turbidity. A very small 

 amount of the crystalline Neroli Camphor then made its appearance, 

 floating on the surface of the liquid ; by re-solution in boiling alcohol 

 it was obtained in crystals of rather indistinct form. The re-distilled 

 oil gave no camphor whatever. 



Neroli Camphor was first noticed by Boullay in 1828. According 

 to our observations it ^is a neutral, inodorous, tasteless substance, 

 fusible at 5.5" C, and forming on cooling a crystalline mass. The 

 crystallization should be eflected by cooling the hot alcoholic solution, 

 no good crj^stals being obtainable by slow evaporation or by sublima- 

 tion. The produce was extremely small, about 60 grammes of oil 

 having yielded not more than 01 gramme. Perhaps this scantiness of 

 produce was due to the oil being a year and a half old, for according to 

 Plisson^ the camphor diminishes the longer the oil is kept." We were 

 unable to obtain any .similar substance from the oils of bergamot, petit 

 grain, or orange peel. 



Orange Fioxver Water is a considerable article of manufacture 

 among the distillers of essential oils in the south of Europe, and is 

 imported thence for use in pharmacy. According to Boullay* it is 

 frequently acid to litmus when first made, — is better if distilled in 

 small than in large quantities, and if made from the petals per se, 

 rather than from the entire flowers. He also states that only 2 lb. of 

 water should be drawn from 1 lb. of flowers, or 3 lb. if petals alone are 

 placed in the still. As met with in commerce, orange flower water is 

 colourle.ss or of a faintly greenish yellow tinge, almost perfectly trans- 

 parent, with a delicious odour and a bitter taste. Acidulated with 

 nitric acid, it acquires a pinkish hue more or less intense, which dis- 

 appears on saturation by an alkali. 



Uses — Oil of Neroli is consumed almost exclusively in perfumery. 

 Orange flower water is frequently used in medicine to give a pleasant 

 odour to mixtures and lotions. 



Adulteration — The large variation in value of oil of Neroli as 

 shown by price-currents* indicates a great diversity of quality. Besides 

 being very commonly mixed, as already stated, with the distilled oil of 



' Joiim. de Pharm. xv. (1829) 152. * Thus in the price-list of a firm at Grasse, 



' Yet we extracted it from an old sample Neroli is quoted as of four qualities, the 



labelled "Essence de N6roli Portugal — lowest or '•commercial" being leas than half 



M&ro." the price of the finest. 

 ^ Bulletin de Pharm, i. (1809) 337-341. 



