340 DECAY OF WOODY FIBRE. 



of wood into humus might be viewed as a removal of the elements 

 of water from the carbon. 



The analysis of mouldered oak-wood, taken from the interior 

 of the trunk of an oak, and possessing a chocolate-brown color 

 and the structure of wood, showed that 100 parts of it contained 

 53-36 parts of carbon and 46*44 parts of hydrogen and oxygen 

 in the same relative proportions as in water. From an examina- 

 tion of mouldered wood of a light-brown color, easily reducible 

 to a fine powder, and taken from another oak, it appeared that it 

 contained 56*211 carbon and 43*789 water. 



These indisputable facts point out the similarity of the decay 

 of wood, with all other instances of the slow combustion or oxi- 

 dation of bodies containing a large quantity of hydrogen. Viewed 

 as a kind of combustion, it would indeed be a very extraordinary 

 process, if the carbon combined directly with the oxygen ; for 

 it would be a combustion in which the carbon of the burning 

 body augmented constantly, instead of diminishing. Hence it is 

 evident that it is the hydrogen which is oxidized at the expense 

 of the oxygen of the air ; while the carbonic acid is formed from 

 the elements of the wood. Carbon never combines at common 

 temperatures with oxygen, so as to form carbonic acid. 



In whatever stage of decay wood may be, its elements must 

 always be capable of being represented by their equivalent 

 numbers. 



The following formulae illustrate this fact with great precision : 



C 3(J H 2 2 2 — oak wood, according to Gay-Lussac and Th*Snard.* 

 C g g H 2 2 — humus from oak-wood (Meyer). f 



C 34 H 18 ,3- » » (^ Will.); 



It is evident from these numbers, that for every two equiva- 

 lents of hydrogen oxidized, two atoms of oxygen and one of car- 

 bon are set free. 



Under ordinary circumstances, woody fibre requires a very 

 long time for its decay; but this process is of course much 



* The calculation from this formula gives 52*5 carbon, and 47*5 water 

 f The calculation gives 54 carbon, and 46 water. 

 X The calculation gives 56 carbon, and 44 water. 



