SOS EREMACAUSIS, OR DECAY. 



-ed. Now, the only changes which take place here are, that the 

 absorption of oxygen by the elements of orcin and ammonia 

 causes the formation of water ; 1 equivalent of orcin C l8 H, , 

 7 , and 1 equivalent of ammonia NH 8 , absorb 5 equivalents 

 of oxygen, and 5 equivalents c>f water are produced, the compo- 

 sition of orcein being C^ H 9 7 N. (Dumas.) In this case 

 it is evident, that the oxygen absorbed has united merely with 

 the hydrogen. 



But, although it appears very probable that the oxygen acts 

 primarily and principally upon hydrogen, the most combustible 

 constituent of organic matter in the state of decay ; still it can- 

 not thence be concluded that the carbon is quite devoid of the 

 power to unite with oxygen, when every particle of it is surround- 

 ed with hydrogen, an element with which the oxygen combines 

 with greater facility. 



We know, on the contrary, that although nitrogen cannot be 

 made to combine with oxygen directly, yet it is oxidized 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 oxidized in several cases, obtaining 

 from its contact witli 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 con- 

 taining 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 saliculite of potash. This salt, 

 when exposed to a moist atmosphere, absorbs 3 atoms of oxygen ; 

 melanic acid is produced, a body resembling humus, in conse- 

 quence 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 atmo- 

 sphere of oxygen, 0*2 grm. absorb 28-6 cubic centimeters of 

 oxygen gas in twenty-four hours, the alkali acquiring at the same 

 time 6 cubic centimeters of carbonic acid. (Chevreul.) But 

 these 6 cubic centimeters of carbonic acid contain only an equal 

 volume of oxygen, so that it is certain from this experiment that 



