140 Intelligence and Miscellaneous Articles. 



the bottom of the vessel, which is citric aether ; it must be repeat- 

 edly washed with cold water, and afterwards with a dilute alkaline 

 solution. When the liquid which floats upon the aether leaves no 

 residue on drying, the washing is to be discontinued, and the aether 

 is to be dissolved in alcohol ; this solution, which has considerable 

 colour, is to be digested with pure animal charcoal : it is then to be 

 filtered, and the desiccation is to be finished in vacuo. If 8 T 6 ^oz. 

 avoirdupoise be employed, the experiment requires only about an 

 hour for its completion, and the product amounts to above 5^ oz- 

 Pure citric aether is liquid, transparent, of an oily consistence, and 

 a yellowish colour. Its smell somewhat resembles that of olive oil, 

 its taste is bitter and disagreeable, and its density 1*142 ; it is vo- 

 latile, but the temperature at which it volatilizes is so near that at 

 which it decomposes, that it cannot be distilled without the decom- 

 position of a large portion of it. If it be heated in an open vessel, 

 it emits a very dense vapour, which inflames on the approach of 

 flame, and a coaly residue is left. In close vessels it begins to lose 

 its limpidity at about 248° Fahrenheit, becomes reddish at 518°, 

 and begins to boil and to decompose at about 542°; an oily matter 

 being disengaged, afterwards dilute alcohol, lastly carburetted gases 

 and citric aether [acid ?] ; the residue is charcoal. 



Citric aether is perfectly neutral, leaving no residue after combus- 

 tion ; it is soluble in aether, in weak alcohol, and even slightly so 

 in water. An aqueous solution of citric aether becomes acid after 

 some time, and much more quickly so if heated. If citric aether be 

 boiled with a solution of potash or soda, alcohol is obtained, with 

 citrate of the alkali. Solution of ammonia has no immediate action, 

 nor has the dry gas. Neither barytes nor strontian water render 

 either citric aether, or a fresh solution in water, turbid. Nitric 

 acid dissolves it cold, and if the solution be poured into water, the 

 aether does not separate. When the nitric solution is gently heated, 

 a brisk action occurs, which goes on spontaneously ; there is a dis- 

 engagement of red vapours, and the residue has a smell resembling 

 that of hyponitrous acid. If considerable quantities be acted upon, 

 and the ebullition be long continued, oxalic acid is found in the re- 

 sidue; this residue, which is slightly yellow, becomes of a deep red 

 when saturated with ammonia. 



Concentrated sulphuric acid immediately imparts colour to citric 

 aether; it dissolves it cold, but quits it on the addition of water, and 

 the aether is unchanged. The sulphuric solution when heated to 

 about 158°, begins to exhibit appearances of a reaction, which be- 

 comes extremely strong as the temperature increases ; there is a 

 disengagement of alcohol and sulphuric aether, and the residue is 

 red, transparent, very thick, and soluble in water. 



Hydrochloric acid dissolves citric aether cold, as the other two 

 acids do, and quits it on the addition of water. The hydrochloric 

 solution does not exhibit any appearance of reaction; the liquid 

 boils, hydrochloric aether is disengaged ; a little alcohol, and no citric 

 Kther, remain in the residue. 



Potassium put in contact with citric aether occasions disengage- 

 ment of a gas • but the .action stops as soon as the surface of the 



