366 DECOMPOSITION OF WOOD, COAL, ETC. 



The white decayed wood found in the interiors of 

 trunks of dead trees which have been in contact with 

 water, is produced in the way just mentioned. 



An analysis of wood of this kind, obtained from 

 the interior of the trunk of an oak, yielded, after 

 having been dried at 212^, 



Carbon 48-11 . . . 48-14 



Hydrogen 6-31 . , 606 



Oxygen 4531 .  . 44-43 



Ashes 1-27 . . 1-37 



10000 100-00 



Now, on comparing the proportions obtained from 

 these numbers with the composition of oak wood, ac- 

 cording to the analysis of Gay-Lussac and Thenard, 

 it is immediately perceived, that a certain quantity 

 of carbon has been separated from the constituents 

 of wood, whilst the hydrogen is, on the contrary, in- 

 creased. The numbers obtained by the analysis cor- 

 respond very nearly to the formula C33 H27 024.* 



The elements of water have, therefore, become 

 united with the wood, whilst carbonic acid is disen- 

 gaged by the absorption of a certain quantity of 

 oxygen. 



If the elements of 6 atoms of water and 3 atoms 

 of oxygen be added to the composition of the w^oody 

 fibre of the oak, and 3 atoms of carbonic acid de- 

 ducted, the exact formula for white mouldered wood 

 is obtained. 



Wood C36H22 022 



To this add 5 atoms of water , . H 5 O 5 



3 atoms of oxygen ... O 3 



C36 H27 O 30 

 Subtract from this 3 atoms carbonic acid C 3 O 6 



C33 H27 024 



The process of mouldering is, therefore, one of 

 putrefaction and decay, proceeding simultaneously, 

 in which the oxygen of the air and the component 



* The calculation from this formula gives in 100 parts 47-9 carbon, 

 6-1 hydrogen, and 46 oxygen. 



