^^ IntelliggtiQe^and MisceUaneQm.Afticles. 



and yields a syrupy,li(iviifl Jeseffii^^ng, burnt sugar in appearance; it»j 

 melting-point is lower tlian that of salicine ; on cooling after meltiiigi 

 it retains itg transparency and becomes brittle like resin ; if, on the 

 contrary, the action of heat upon it be continued, it decomposea^^ 

 yielding^a vapour which reddens liti^us paper ; when rubbed with Ag 

 little jjotash and heated in a tube so as to be decomposed, it does 

 not restore the blue colour of reddened litmus ; when heated on pla- 

 tinum foili it burns without lejlving anyresidue. Cascarilline is soluble 

 in alcohol and aether, but is very slightly soluble in waterj biife never- 

 theless imparts strong bitterness to it ; the solution does not alter 

 l^ta^\\^^jafi4 is, not precipitated eitUer by .a^etate;Qr diapetate of ieaii, 

 by tannin or the slk^eSv Qo\^ QQncentrated sulphuric acid ilissolvesj 

 cascarilline and becomes immediately of a deep red colour with a 

 purple tint ; water added to it occasions precipitation ; the liquor 

 then appears of a grass-green colour, which is more or less deep ac- 

 cording to the quantity of water added ; as the precipitate falls the 

 liquor becomes colourless, and the precipitate only retains the green 

 colonr. Excess of ammonia does not dissolve this precipitate, but 

 renders it of an ochre-yellow colour. 



Concentrated nitric acid also dissolves cascarilline ; the solution 

 is yellow and is precipitated by ammonia, excess of which does not 

 dissolve the precipitate. '? 



Hydrochloric acid also dissolves it and becomes of a violet colour,;'^ 

 which the addition of a small quantity of water renders blue, and^T 

 more renders it green. 



As cascarilline contains no nitrogen, and does not combine either ; 

 with acids or alkalies, it must be classed with the neutral non-azotizedi'jl 

 bodies, such as salicine, colombine, &c. — Journ. de Pharm. et de Ch^ 

 Aout 1845. -'sorj xrtr .sm^i yrs .-^>«yrj ,T? 



4i ■ SrHfiAolDAL CONDITION OF tlOXTIDS^^ f, -^^ 



To Richard Taylor, i:sq. ■.:^ M :Mf imSB, 



I cannot think that Mr. Armstrongs explanation 6i the fadt,— t.iT 

 that the temperature of liquids in the above condition is lower than -^ 

 their boiling-point, — is the true one ; or rather, I ought to say, that 

 his paper does not in any way account for the phsenomenon it so .i 

 ably, describes. if 



The separation of the liquid from the dish depends upon the mo- ;':; 

 lecular relations between the liquid and the dish being altered by the- C 

 increased temperature of the latter ; and this is, I think, all that can ;,f^ 

 be said of the matter in the present state of our knowledge. -/S 



But, taking the sepg.ration as a fundamental fact, we must, to ex- 'f 

 plain the diminution of temperature, solve the following problem, at '/ 

 least approximately > — 



" A spheroidal mass of a vaporizable liquid is surrounded by a 

 medium of a temperature t, t varying from point to point ; required 



* Mr. Armstrong's paper to which this note refers will be found at p. 52 

 of the present volume. 



