I EI DEM 459 



Polycliroit was prepared by Weiss in the following manner : 

 *' Saffron was treated with ether, by which fat, wax, and essen- 

 tial oil were removed, and it was then exhausted with water. 

 From the aqueous solution, gummy matters and some inorganic 

 salts were precipitated by strong alcohol. After the separation 

 of these substances, polychroit was precipitated by addition of 

 ether. Thus obtained, it is an orange-red, viscid, deliquescent 

 substance, which, dried over sulphuric acid, becomes brittle and 

 of a fine ruby colour. It has a sweetish taste, but is devoid of 

 odour, readily soluble in spirit of wine or water, and sparingly 

 in absolute alcohol. By dilute acids, it is decomposed into 

 crocin, sugar, and an aromatic volatile oil having the smell of 

 saffron. Weiss gives the following formula for this decom- 

 position : 



Polychroit. Crocin, Essential oil. Sugar. 



6 



Crocin is a red powder, insoluble in ether, easily soluble in 

 alcohol, and precipitable from this solution on addition of ether. 

 It is only slightly soluble in water, but freely in an alkaline 

 solution, from which an acid precipitates it in purple-red flocks. 

 Strong sulphuric and nitric acids occasion the same colours as 

 with polychroit, the former producing deep-blue, changing to 

 violet and brown, and the latter green, yellow, and finally 

 brown. It is remarkable that hydrocarbons of the benzol class 

 do not dissolve the colouring matter of saffron. 



" The oil obtained by decomposing crocin is heavier than 

 water ; it boils at about 209^0., and is easily altered, even by 

 water. It is probably identical with the volatile oil obtainable 

 to the extent of one per cent, from the drug itself, and to 

 which its odour is due. 



"Saffron contains sugar (glucose?) besides that obtained by 

 the decomposition of polychroit. It leaves after incineration 

 5 to 6 per cent, of ash." (Phawiacographia^ p. 604.) 



The investigation of the characteristic constituents of saffron, 

 which had previously occupied the attention of several chemists, 

 has been taken up by Herr Kayser {Berlchte, xvii., 2228). Ey 

 distilling saffron suspended in water in a current of carbonic 



