180 Foreign and Miscellaneous Intelligence. 



Boullay, and gallic acid by Berzelius ; the proportions they obtain 

 are as follow : 



Ulmic Acid. Gallic Acid. 



Carbon . . 56.7 57.08 



Water . . 43.3 42.92 



equal to three proportions oxygen, three hydrogen, and six of carbon. 

 Hence it was supposed, that gallic acid differed only in water of 

 crystallization, but all attempts to deprive it of water, and convert 

 it into ulmic acid, failed. 



The ulmates of the metals, although insoluble in saline so- 

 lutions and in excess of ammonia, are, when well washed, soluble 

 in water, like the ferro-prussiate of iron. They take fire at a tem- 

 perature much below a red heat, and burn. Three of them were 

 found by experiment to be composed, per cent,, as follows : 



Oxide of Silver. Of Lead. Of Copper. 



28.57 . 26.86 . 10.5 

 Ulmic acid 71.43 . 73.14 . 89.5 



Hence the equivalent of the acid consists of fifteen proportions of 

 oxygen, fifteen of hydrogen, and thirty of carbon, which, taking 

 hydrogen as unity, is 315. This is precisely five times the number 

 of gallic acid. 



The feeble capacity of saturation possessed by ulmin may, per- 

 haps, be important in nature, for a large quantity of this food of 

 plants may in consequence be transmitted to them from decomposing 

 substances, by small quantities of alkali or ammonia. The earthy 

 ulmates, and especially that of lime, are not quite insoluble, and 

 withal are capable of being suspended so perfectly in fluids as to 

 be useful in the nutrition of plants, whilst still they are not so likely 

 to be washed away as the soluble ulmates. 



Azulmic Acid. By this name M. Boullay designates a substance 

 which has the same kind of relation to ulmic acid that azoted organic 

 matter has to such as is of vegetable origin. The carbonaceous 

 product left by the spontaneous decomposition of hydrocyanic acid 

 is azulmic acid, and not a carburet of azote. It contains hydrogen, 

 and can combine with salifiable bases in the same manner as hydro- 

 cyanic acid itself. Azulmic acid is not soluble either in hot or cold 

 water or alcohol : strong cold nitric acid dissolves it, forming a 

 reddish solution, precipitable by water. The alkalies dissolve it 

 very freely, producing deep-coloured solutions : the acids precipitate 

 these solutions, as do also the metallic salts. By heat azulmic acid 

 gives first hydrocyanate of ammonia, then cyanogen, and leaves 

 carbon. When analysed, the proportion of azote to carbon was in 

 volumes as 2 to 5. Hence, upon theory, it will consist by weight 

 per cent, of 47.64 azote, 50.67 carbon, and 1.69 hydrogen. 



Pursuing the analogy between ulmic and azulmic acid, M. Boullay 

 endeavoured to form the latter by heating gelatine with potassa, in 

 imitation of M. Braconnot's process for forming ulmin ; and, in 

 fact, azulmic acid appeared to be produced. Azulmic acid is pro- 



