CHEMICAL COMrOSTTlON OF DIGITALIS. 35 



powdered, and the powder of a yollowisli colour, intensely 

 bitter, with a peculiar faint odour, and causing sneezing if it 

 be carelessly moved, heavier thau water, and doubtfully 

 crystallisable. It is unalterable in air, fuses at 100°, and 

 above this becomes coloured and loses its bitterness, which is 

 replaced by an astringent taste. It is neutral to test-paper, 

 but gives off acid fumes when burnt. It contains no nitrogen. 

 It is soluble in nearly 2,000 parts of cold and 1,000 of hot 

 water It is easily soluble in alcohol and wood spirit, in 

 about 100 parts of pure ctlicr, in a considerably larger pro- 

 portion if the ether contain water, and more especially 

 alcohol, completely soluble in chloroform, partly in almond 

 oil and oleic acid, and insoluble in sulphide of carbon. It 

 forms no compounds with acids. Concentrated sulphuric acid 

 forms a brownish solution, becoming somewhat purple, and* 

 depositing olive-coloured flakes o]i the addition of water. 

 With hydrochloric acid it forms a light green liquid, becoming 

 darker as it stands, and lessened but not changed by the 

 addition of water. Its aqueous solution is not precipitated by 

 bichloride of mercury, acetate, or subacetate of lead, nitrate of 

 silver, perchloride of iron, chloride of gold or platinum, or 

 acetate of copper. 



Digitalosc. — This has a wliite crystalline — almost micaceous 

 — aspect. Its point of fusion is 200^, and it is soluble in con- 

 centrated sulphuric acid, giving it a pale yellow colour, but 

 forming with dilute acid a rose-coloured solution. It is neu- 

 tral, tasteless, soluble in alcohol and ether, insoluble in water. 



Digitalin. — This is a white neutral powder, soluble in alcohol, 

 insoluble in water, insipid or faintly bitter ; furnishing to water 

 a transparent ]naterial in which this bitterness resides. Its 

 alcoholic solution is precipitated by caustic potash. 



Digitalide. — This occurs in pale, gummy-looking scales, is 

 neutral, soluble in water and feeble alcohol, slightly in strong 

 alcohol, insoluble in ether. Its taste is sweetish, with a bitter 

 after-taste. Is perhaps the bitter part of digitalis, which is 

 soluble in water, along with colouring matter. It is also 

 precipitated by caustic potash, and distinguished from digitalin 

 by its form. 



D 2 



