NATURE OF THE PROCESS. 265 



be concluded that the carbon is quite devoid of the 

 power to unite with oxygen, when every particle 

 of it is surrounded with hydrogen, an element 

 with which the oxygen combines with greater 

 facility. 



We know, on the contrary, that nitrogen, which 

 cannot be made to combine with oxygen directly, 

 is oxidised and forms nitric acid, when mixed with 

 a large quantity of hydrogen, and burned in oxygen 

 gas. In this case its affinity is evidently increased 

 by the combustion of the hydrogen, which is in 

 fact communicated to it. It is conceivable, that, 

 in a similar manner, the carbon may be directly 

 oxidised in several cases, obtaining from its contact 

 with hydrogen in eremacausis a property which 

 it does not itself possess at common temperatures. 

 But the formation of carbonic acid during the 

 eremacausis of bodies which contain hydrogen, 

 must in most cases be ascribed to another cause. 

 It appears to be formed in a manner similar to the 

 formation of acetic acid, by the eremacausis of 

 saiiculite of potash. This salt, when exposed to 

 a moist atmosphere, absorbs 3 atoms of oxyen ; 

 melanic acid is produced, a body resembling 

 humus, in consequence of the formation of which, 

 the elements of 1 atom of acetic acid are separated 

 from the saliculous acid. 



An alkaline solution of hsematin being exposed 

 to an atmosphere of oxygen, 0*2 Grm. absorb 28*6 

 cubic centimeters of oxygen gas in twenty-four 



