60 



bitter, dissolves readily in water, less so in alcohol, not in ether, is 

 neutral, and contains no nitrogen. 



CrOCill=C58 H42 O30. The yellow pigment of the stigmata of 

 Crocus sativxxs and of the fruits of Gardenia grandiflora, also occur- 

 ring in Fabiana imbricata. Remove the fat substances of saffron 

 by ether, boil with water, precijiitate the decoction with sab- 

 acetate of lead, wash the deposit, and decompose under water by 

 sulphuret of hydrogen, collect the sulphide of lead which retains 

 the C, treat with boiling alcohol, and evaporate the solution. — 

 Bright-red powder, without odour, decomposes above 100°, dis- 

 solves in water with orange colour, readily in alcohol, with gi^eat 

 difficulty in ether, readily in diluted alkalies, turns blue with 

 concentrated sulphuric, green with nitric, black -brown with hydro- 

 chloric acids; changes when heated with diluted acids into sugar, 

 and a deep-red powder, which is sparingly soluble in water 

 (Crocetin). 



CrotOll Oil. Obtained by pressing the seeds of Croton Tiglium. 

 Brown, of thick fluidity and of very rancid odour, irritates strongly 

 the skin, and acts as a drastic ; becomes turbid at a moderate cold, 

 and slowly changes at the air to a thick, viscous mass. Dissolves 

 in twenty-three parts alcohol of 85°/^, is not solidified by hypo- 

 nitric acid. It contains Crotonol (substance irritating the skin), 

 a product of decomj^osition of the latter, causing the smell, and as 

 glycerids: stearic, palmitic, myristic and laui-ic acids; two or 

 more liquid acids belonging to the same series as oleic acid, but 

 differing from the latter; also, angelic [Tiglinic acid, according to 

 Genther and Froehlich] and crotonic acids. A mixture of the two 

 latter acids appears to constitute the latrophic acid of Pelletier 

 and Caventon, and the Crotonic acid of the earlier chemists. 



Crotonol = Cis Hh O 4 . In the fat-oil of the seeds of Croton 

 Tiglium, forming 4°/^ of the oil ; is the ingredient which irritates 

 the skin, but not the drastic principle. Shake the oil with an 

 alcoholic solution of caustic soda sufficient to form an emulsion ; 

 warm gently for a few hours, add water or a solution of common 

 salt, and remove the oil, which will form on the svirface, by repeatedly 

 filtering through wet papei'. The aqueous liquid, when mixed 

 with water and hydrochloric acid, separates another oil which is 

 to be dissolved in cold alcohol, digested with hydrated oxyd of 

 lead until the acid i-eaction has disappeared (whereby a flocky, 

 afterwards conglutinating preci2:)itate is formed), and mixed with a 

 little cavistic soda and much water. A milky liquid is produced, 

 which becomes clear after the oil has subsided. Wash the latter, 

 first by itself, and afterwards dissolved in ether, with water, and 

 evaporate the ethereous solution in a vacuum. The Crotonol 

 remains pure. Coloiivless or slightly wine-yellow, viscid, turpen- 

 tine-like mass of a faint, peculiar odour ; not distillable, is changed 



