196 Dr. Stenliouse on some of the 



100-00 100-00 100-00 

 The salt employed in these determinations was prepared at 

 three or four different times; but though the results agree 

 pretty closely, I have not been able to fix upon a probable 

 formula for the salt. 



When meconic acid is agitated in the cold with freshly pre- 

 cipitated peroxide of iron no eff'ect is produced, and if a slight 

 heat is applied, only a very partial combination is effected. 

 If the heat is increased, though much under 212°F., a large 

 portion of the peroxide is dissolved by the acid ; but if the 

 compound is examined, much of the iron has been reduced to 

 the state of protoxide. If the liquid is filtered, it deposits on 

 cooling a quantity of a reddish powder, which consists of me- 

 conic acid in combination with a mixture of peroxide and pro- 

 toxide of iron ; sometimes the oxide amounts to as much as 

 34 per cent. 



Komenic Acid. 



This acid is easily prepared by boiling meconate of lime in 

 a great excess of strong muriatic acid. This removes almost 

 the whole of the base, and converts the meconic into the ko- 

 menic acid. When the solution cools the impure acid is de- 

 posited in hai'd reddish coloured crystals. The best way of 

 purifying the komenic acid is to dissolve it with the assistance 

 of heat in a slight excess of a concentrated solution of either 

 potash or soda, and to filter the liquid while hot. This re- 

 moves any portion of lime which the komenic acid may still 

 have retained. On the cooling of the solution the komenate 

 of potash crystallizes in white mammillated masses. These 

 should be washed with a little cold water till the highly- 

 coloured mother liquor is entirely removed. The salt is then 

 easily decomposed by boiling it with an excess of pure muri- 

 atic acid, from which the komenic acid may be freed by two 

 or three crystallizations. Komenic acid, even when pure, has 

 usually a slight shade of reddish-yellow. This may be almost 

 entirely removed by digesting the acid with purified animal 

 charcoal. When heated on platinum foil it does not leave 

 any residue. 



Komenate of Ammonia. 



When a slight excess of ammonia was added to a hot solu- 

 tion of komenic acid it immediately became of a pale yellow 



