330 Intelligence and Miscellaneous Articles . 



Several analyses made according to this method yielded highly 

 satisfactory results. 1*771 grm. of recently ignited carbonate of 

 potash, which was allowed to cool in a closed platinum crucible, gave 

 0*564- carbonic acid. Taking the atom of potash at 590, that of the 

 carbonic acid at 275, 0*563 ought to have been obtained. 



1*705 grm. of very pure magnesite gave 0*870 carbonic acid 

 = 51*026 per cent. — Poggendorff's Annalen, No. vi. 1846. 



ON THE ACTION OF NITRIC ACID UPON CHOLIC ACID. 

 BY A. SCHLIEPKR. 



The interesting connexion which has recently been shown to exist 

 between the products of decomposition of cholesterine and choloidic 

 acid by Prof. Redtenbacher*, led to the supposition that it might 

 also extend to the other products of the bile if they were submitted 

 to a similar treatment. With this view I have been induced to 

 examine the action of nitric acid on Demarcay's cholic acid. 



The cholic acid was prepared according to the process described 

 by Theyer and Schlosser ; bile, freed from mucus, fat and colouring 

 substance, was retained for several days at a boiling temperature 

 with a tolerably strong solution of potash, and then concentrated 

 until a soapy mass, which became hard on cooling, separated from 

 the .liquid. After complete separation, it was dissolved in water, 

 filtered, and treated with acetic acid, which separates the impure 

 cholic acid in thick white flakes, which unite, forming resinous 

 masses. If the eliminated resin be heated with water to boiling, it 

 assumes all at once a granular crystalline structure, and is then 

 easily reduced to powder ; the latter was dried, and washed on a 

 funnel with aether until it appeared white, and then pure white cho- 

 lic acid obtained from it by dissolving and crystallizing it from 

 alcohol. Cholic and nitric acids do not act on one another in the 

 cold, however concentrated the latter may be ; but if a mixture of 

 the two be heated in a retort, a very violent reaction soon ensues, 

 the mass ascends, frothing considerably, while large quantities of 

 nitrous acid escape. When the first action is over, the retort con- 

 tains a dark yellow liquid, on which float some drops of oil, which 

 on cooling solidify, and are nothing more than unaltered cholic 

 acid. As the nitric acid which distilled over possessed a peculiar 

 odour, it was nearly saturated with an alkali and again distilled ; 

 but although the aqueous distillate still retained the peculiar smell, 

 none of the volatile products which Redtenbacher discovered in 

 submitting cholesterine and choloidic acid to a similar treatment, 

 could be detected in it. The yellowish liquid which remained in the 

 retort was evaporated on the water-bath to expel the excess of nitric 

 acid, when it dried to a yellowish transparent gum, which exhibited 

 in its external properties the greatest resemblance to the cholesteric 

 acid recently described by Redtenbacher. To separate this body 

 from some still undecomposed cholic acid, it was repeatedly dis- 

 solved in water, filtered, and again evaporated until the residue dis- 



* Chem. Gaz., vol. iv. p. 269. 



