Salts ofMeconic and Komenic Acids. 195 



The salt employed in these determinations was made at five 

 different times. The compound is evidently a double salt, 

 consisting of meconate of iron and meconate of ammonia. 

 The discrepancies in the determinations are probably owing 

 to the circumstance that one of the constituent salts is more 

 soluble in the wash- water than the other. 



Iron Salt from Ethereal Solution of Meconic Acid. 



A cold ethereal solution of meconic acid was made by agita- 

 ting the acid, in the state of fine powder, in a stopped bottle 

 with anhydrous aether. A considerable quantity of aether 

 must be employed, as the meconic acid is but very slightly so- 

 luble in that liquid. The saturated solution was then filtered 

 into a second bottle, containing an ethereal solution of per- 

 chloride of iron. This was made by dissolving neutral per- 

 chloride of iron, which had previously been gently evaporated 

 to dryness, in anhydrous aether. When mixed, the two li- 

 quids became of a deep red colour, and in a few minutes a 

 quantity of reddish-brown flocks precipitated. These were 

 collected on a filter and washed with aether till any adhering 

 chloride of iron was removed. When dried they formed a 

 reddish-brown powder. This can only be obtained by the 

 use of anhydrous aether ; if it contains any water, no precipi- 

 tate falls, and the salt is condensed in blood-red drops on the 

 sides of the bottle. The presence of alcohol is equally ob- 

 jectionable. After the salt has been dried it becomes much 

 less soluble than before. It dissolves pretty readily in cold 

 water and alcohol, but more readily in hot water, and the ad- 

 dition of a little acid greatly increases its solubility. The co- 

 lour of its solution is brownish-red. When it is treated with 

 a slight excess of potash or soda it is instantly decolorized, 

 and the iron precipitated in the state of peroxide. The iron 

 of this compound is not precipitated by an excess of ammo- 

 nia, and its colour is only changed to a deep yellowish-red. 

 Dried at 212^ F.,— 



I. 0-3826 salt gave 0'117 peroxide = 30*58 per cent. 



II. 0-2705 ... 0-082 ... = 30'31 



III. 0-2307 ... 0-0721 ... = 31-25 



IV. 0-2593 ... 0-0803 ... = 30*96 

 V. 0-3131 ... 0-972 ... = 31^03 



Mean 30-82 



I. 0-2747 salt gave 0-261 carbonic acid and 0-0475 water. 



II. 0-44-1 ... 0-41 0-0755 ... 



III. 0-345 ... 0-325 0*054 ..♦ 



02 



