Intelligence and Miscellaneous Articles. 171 



salts of iron also precipitate it ; and when a solution of chloride of iron 

 is mixed with one of euchroic acid, no change is produced till an al- 

 kali is added, and then a bulky precipitate of a beautiful blue colour 

 is formed. — L'Institut, No. 383. 



SEPARATION OF GOLD AND PLATINA. 



Mr. Kemp has found that oxalic acid reduces the solutions of 

 gold, and has no action on those of platina. To separate these two 

 metals, therefore, and to determine their quantities, a solution may 

 be made in aqua regia and the gold precipitated by oxalic acid in the 

 metallic state, and the platina by formic acid. The difficulty of se- 

 parating these two metals which has hitherto existed, renders this 

 process of considerable importance. — Journal de Fharmacie, Jan, 

 1842. 



LITHOFELLIC ACID. 



M. Gobel has discovered in a biliary calculus, deposited in the 

 Zoological Cabinet of Dorpat, a new body, to which he has given the 

 above name. In order to obtain it, he dissolved the calculus in boil- 

 ing alcohol of 99 per cent., and he slowly evaporated the filtered 

 liquor, which was of a greenish -browTi colour ; solid crystalline de- 

 posits of the same colour were formed, which were powdered and 

 treated repeatedly with cold alcohol : by this process he succeeded 

 in extracting the more soluble colouring matter of the bile, and ob- 

 tained a yellowish powder ; this being re-dissolved in boiling alcohol, 

 the lithofellic acid was separated by slow evaporation in the form of 

 crystalline crusts ; the crystals are rhombic prisms, terminated by an 

 oblique surface ; when these are examined with a glass some of them 

 are entirely colourless. 



Lithofellic acid dissolves in 294 parts of alcohol of 99 percent, at 

 68° F., and in 65 parts of boiling alcohol ; it requires 444 parts of 

 absolute aether at 68° F., and 47 parts at a boiling heat. It fuses at 

 400° F. into a liquid of a slight yellow colour, and forms after cool- 

 ing a solid mass, which is colourless and crystalline. When heated 

 in a small retort this acid emits white vapours, which condense into 

 a yellowish liquid, and gives a mixture of empyreumatic oil and a 

 little acidulous water. The distilled product has a penetrating odour 

 resembling that of oil of amber ; a very small quantity of carbon re- 

 mains in the retort. This empyreumatic product appears to contain 

 a new acid ; it forms a soap with potash, which is decomposed by 

 hydrochloric acid. 



When the lithofellic acid is treated with a solution of potash or 

 soda, saj)onification soon takes place if the solutions are strong and 

 the soap separates ; but if the solution be dilute, the soap dissolves 

 in and separates only on concentration. 



The soap floats on the surface in the state of a fluid mass, of a 

 light yellow colour, as long as the liquor is hot. On cooling it forms 



