BY JOSEPH LAUTERER, 11. D. 73 



acid, with claret colour, and with a pale yellow colour in alcohol, 

 ether, and chloroform. Cold water, caustic potash solution, and 

 benzol have no apparent action on it. The alcoholic solution 

 of the resin is stained bluish -brown by an alcoholic solution of 

 ferric chloride. Caustic potash in spirits stains it greenish 

 yellow. 



If boiled in water the resin gives off to it a body, which 

 changes the clear colour of the water to a brilliant iridescence 

 of peacock blue, looking in the reflected light exactly like the 

 green lakes so renowned for their beauty in the hot lake district 

 of New Zealand. 



The body which causes this brilliant iridescence Avas found 

 to crystallize from the water after cooling, in rhombic needles, 

 which on combustion gave figures pointing to the formula 

 ■CpHyO^, sliowing the identity of the substance in question 

 with umbelliferone, a body the constitution of which is that of 

 oxycoumarin, C, H,, H ( C H : C H— C 0). 

 lO 



The fluorescence in the Evodia resin solution, caused by the 



umbelliferone is destroyed immediately by ferric chloride, cupric 

 sulphate, sal ammoniac, and the least trace of an organic or 

 inorganic acid (including boric acid), so that the infusion is as 

 good a reagent for acids as an alkaline solution of phenolphthalein, 

 and a much better one than the test papers of litmus and 

 turmeric. Tbe addition of some alkaline solution after the acid> 

 restores the fluorescence immediately, but after some hours it 

 vanishes again. 



Permanganate of potassium is reduced by an umbelliferone 

 solution, without destroying the fluorescence. Iodine, chloride 

 of lime, and borax have no action on the fluorescence at all. 



The fluorescent solution absorbs the violet and blue rays in 

 the spectroscope. 



Hitherto ready -formed umbelliferone has only been found 

 in the resin of umbelliferous plants, i.e., in the gum resin of 

 Ferula (lalhanifiua (the so-called Galbanum), and in that of 

 Ferula Asaf/etida, but in none of them in such a large quantity 

 as in the Evodia resin. 



Dry distillation of many resins yields umbelliferone. There 

 are more afiinities between Evodia and the Umbelliferae, which 

 will be pointed out another time. 



