456 ODOROGRAPHIA. 



hydriodic acid. The ultimate effect of oxidising agents upon irene 

 is the production of ioniregene-triboxylic acid, C^o ^12 ^fj- 



Experimenting with a view of obtaining Irone synthetically, 

 Tiemann and Krliger state that an isomeric Ketone lonone, 

 C1.3H20O, having also a violet odour, can be obtained from 

 Citral : — " The aldehyde (citral) is converted by the action of 

 alkalies with acetone into a ketone C\.jHooO, pseudo-iononc, 

 boiling at 14:o^-145^ C, under a pressure of 12 m. m. Sp.gr. 

 09044, index of refraction iij, =-1-5275. This body has a peculiar 

 and very characteristic odour. By the action of dilute acids it is 

 converted into the isomeric ketone lonone. Pure ionone agrees 

 with the formula Cjo H20 0, and under a pressure of 16 m. m. it 

 boils at 126^-128^ C. ; its sp. gr. is 0-9351 and its index of 

 refraction n^ = 1-507. By submitting it to the action of hydriodic 

 acid at rather a high temperature, ionone loses the elements of 

 water and yields a liydrocarbon, CjoHig loncne. By careful 

 oxidation (employing at first feeble reagents and gradually of 

 successively greater strength, ionene is converted into ioniregene- 

 triboxylic acid, which is identical with the product obtained by 

 similarly oxidising the isomeric hydrocarbon Irene as above 

 described. 



Oil of Amber is a product of the dry distillation of amber.* 

 Coarse pieces of amber are distilled in an iron retort, either alone 

 or reduced to powder and mixed with sand. The crude product 

 consists of a mixture of water, succinic acid and oil of amber. 

 On standing it separates into three layers, the lowest consisting of 

 water, the next containing the bulk of the succinic acid, whilst 

 the upper layer contains the oil of amber. By drawing off the 

 oil thus collected, it is obtained as a dirty brown, fluorescent 

 liquid, possessing a nauseating odour. It is insoluble in water, 

 1»ut soluble in alcohol, ether, benzene, and many other solvents. 

 The oil is scarcely acted upon by dilute mineral acids, but 

 concentrated sulphuric and nitric acid re-act violently wdth it. 

 By the action of nitric acid, much succinic acid is produced, and 

 an orange-coloured resin possessing a strong odour of musk is 

 produced, which is used as an " artificial musk." Eeducing agents 



* This paragraph .should liave Leen inserted in the Section on " Empy- 

 reumatic Oils." 



