18 BULLETIN 947, IT. S. DEPARTMENT OF AGRICULTURE. 



remains on the filter paper is washed with water, dried at ordinary 

 temperature, and extracted with warm alcohol, which dissolves the 

 dugaldin with a little coloring matter and sugar. The alcoholic 

 solution is evaporated to dryness at a low temperature; the residue 

 is treated with absolute alcohol, and the solution is filtered off. This 

 is boiled with a little fresh animal charcoal, filtered, cooled, and a 

 large volume of ether is added, when the glucosid precipitates out 

 in white flocks. The yield is less than 0.01 per cent of the green 

 leaves taken. 



As thus prepared dugaldin is a white, amorphous substance sol- 

 uble in alcohol; less soluble in water, chloroform, acetone, and pyri- 

 dine; sparingly soluble in acetic ether; insoluble in ether, benzene, 

 and petroleum ether. It is soluble in aqueous solutions of the alka- 

 lies and forms a slightly soluble compound with lead. Its barium 

 salt is insoluble in alcohol. The glucosid is readily decomposed; 

 when treated with acids or on heating with water it hydrolyzes, 

 yielding a sugar which reduces Fehling's solution in the cold, and a 

 brown resin which is still being studied. Attempts to crystallize 

 the glucosid in quantity have not been successful. 



Reactions of the glucosid. — Ferric chlorid gives no coloration. 

 Tannic acid precipitates the glucosid from its solutions. Bromin 

 water precipitates an addition compound which is soluble with decom- 

 position in hot water. On acetylation the glucosid is decomposed. 

 Acid solutions of the glucosid form a cloud with Mayer's solution. 

 Uranyl acetate produces a transient precipitate insoluble in alkalies 

 and soluble in hydrochloric acid. Potassium permanganate is imme- 

 diately reduced. Cold chromic-acid mixture gives no change, but 

 on heating, the mixture is completely reduced, forming a green solu- 

 tion. A mixture of hot nitric and sulphuric acids nitrates the glu- 

 cosid, forming a yellow solution. On dilution with water a yellow 

 nitro derivative is precipitated which is soluble in alkalies. 



Chemical Experiments. 



The material used for the chemical examinations was collected 

 at the experiment station, Salina, Utah. When green material 

 was used, it was collected and ground through a meat chopper 

 immediately before being used. The dry material used was air- 

 dried under cover until the weight was nearly constant. It was 

 then preserved in cloth bags. 



1. Moisture, ash, extract. — Air-dried samples of radical leaves in 

 No. 60 powder were used for the following determinations: 



Per cent. 



Moisture 9. 70 



Ash 16. 86 



