140 ODOROGRAPHIA. 



The exports from Morocco are about a tenth of those from 

 India. 



Germany is by far the largest consumer, France and Spain 

 ranking next. 



The height of the plant is about one to two feet ; it is 

 characterised by the presence of both general and partial 

 involucres, the latter one-sided ; by the calyx having five lance- 

 shaped teeth. The fruits somewhat resemble in size and shape 

 those of fennel, but usually have the ridges finer, more numerous, 

 and covered w4th minute bristles. They also resemble the fruit of 

 the caraway, but are larger and of lighter colour, and with 

 nine in place of five ridges on each half of the fruit. 



The yield of volatile oil is 3 per cent, from the Mogador fruit ; 

 3'5 from the Maltese; 3 to 4 from the Syrian; and 2-25 to 3 from 

 the East Indian. The sp. gr. at 15^ C. varies from 0-890 to 0-930. 

 Cumin oil consists of a mixture of about 44 per cent, of Cymene 

 (sometimes called Cymol, Hydride of Thymyl and Hydride of 

 Cymyl), Q^^H^^ and 56 per cent of Cwniiiiol (also called 

 Cuminaldehyde and Hydride of Ciimyl) C^^H^.^O. These two 

 bodies also occur in different quantities and proportions in ''Eoman 

 Cumin Oil " (an exotic growth of the same plant, Cuminum 

 Cyminum, Lin.) ; in the oil of the seeds of Cicuta viroscc (Water 

 Hemlock)* ; in oil of Thymus vulgaris (common Thyme) ; in oil 

 of Thymus serpiUum (Wild Thyme) ; in oil of Ptychotis ajoumn 

 (True Bishop's Weed) ; in oil of Satureja hortensis (Pepper-wort) ; 

 and in oil of Euccdyptus ylolulus. They also occur in lesser 

 quantity in oil of ginger, oil of nutmeg, oil of citron and oil of 

 sage. 



Cymene gives a characteristic absorption spectrum, by means of 

 which it can be detected in essential oils. It is unalterable by 

 contact with air, is insoluble in water, but readily soluble in 

 alcohol, ether and essential oils. 



Although more volatile then cuminol and easily separable from 

 the crude oil of cumin by fractional distillation, it is contaminated 

 with a small quantity of cuminol, therefore, to isolate it in purity 

 the first portion of the distillate should be rectified over melting 

 potash ; this converts the cuminol present into cuminate of 



* Ann. der Chem. und Pharni., cviii., p. 386. 



