Intelligence and Miscellaneous Articles. 147 



acid was precipitated by chloride of barium ; the hydrogen and car- 

 bon were determined in the usual manner. 

 It appeared to be composed of — 



Sulphur 23-18 20(H) 



Carbon 34-77 3000 ft ui 



Hydrogen 7-28 62-5 



Oxygen 34-77 , 3000 



Tob^oo 



Its formula is SO 2 O H' J O. 



In the state of vapour calculation gives — 



2 volumes of Sulphurous acid . . 4424 



4 ... Carbon S'318 



10 ... Hydrogen 0'691 



1 ... Oxygen 1-106 



— '- — =4769 



The formula SO* C 4 H 5 O represents, therefore, 2 volumes of va- 

 pour, the same as carbonic aether, CO 2 C 4 H 5 O. It is to be observed 

 that carbonic acid and sulphurous acid have corresponding formulas, 

 and both contain a volume of oxygen equal to their own. — Ann. de 

 Ch. et de Phys., Mai 1846. m6a «s ,. 







ON THE PREPARATION AND PROPERTIES OF DIGITOLE1C ACID 

 AND ITS SALTS. 



M. C. Ph. Kosraann prepared this acid from the Digitalis purpurea 

 by digesting the leaves of the plant in cold water and treating the 

 solution with tri-acetate of lead slightly in excess ; the precipi- 

 tate obtained was boiled for a quarter of an hour with a solution of 

 carbonate of soda ; the filtered solution, which was of a brown co- 

 lour, was treated with dilute sulphuric acid ; the flocculent precipi- 

 tate obtained was perfectly washed and dried, and treated with alco- 

 hol ; the alcoholic solution left by evaporation a residue, which be- 

 came a crystalline mass ; this was six times treated with cold aether, 

 which dissolved a green oil that remained after the evaporation of 

 the aether. This last left a substance A, undissolved. The green 

 oil becomes a granular crystalline mass, and is covered with groups 

 of small stellated needles of a green colour, which have a bitter acrid 

 burning taste, and occasion headache ; the odour is aromatic and not 

 disagreeable ; it melts at 86° Fahr., forming greasy spots on paper ; 

 it is but slightly soluble in water, but dissolves readily in alcohol 

 and in aether. In order to obtain it pure, it is to be combined with 

 bicarbonate of soda in solution, which dissolves it, then precipitated 

 by acetic acid, carefully washed, treated with aether, and to be evapo- 

 rated ; the alcoholic solution reddens litmus paper, and decomposes 

 the carbonate of potash with the effervescence of carbonic acid gas. 



The facts detailed prove that this oily substance is a true acid, to 

 which the author has given the name of digitoleic acid ; and he at- 

 tempted to determine its equivalent by means of the salts of lead and 



L 2 



