Compound Celluloses 183 



substance. The following observations may be cited (loc. dt. 

 p. 225) : 



Wood of Quercus nigra. 



Furfural 



2-12 years old ..... icr6 p.ct. 



69 ..... 10-5 



109-110 ..... 10-3 



Liriodendron tulipifera. 



19-21 years old ..... 9-8 p.ct. 



59-60 . . . . . 9-4 



Magnolia acuminata. 



Year rings of this tree not distinctly discernible. 



Younger than 10 years . . 8 '8 p.ct. 



Old heart wood . . ' . . 8-4 



Platanus occidentalism 



4-10 years old ..... 9-8 p.ct. 



71-79 (Heart wood) . . 97 



Prunus pennsylvanica. 



f(l) 4-12 years old .... JO -8 p.ct. 



'(2) . . . . 10-4 



(1) 60-70 ..... 9'8 



(2) , ..... 9-6 ,, 



In the a.bove it will be observed there is a slight diminution 

 in the furfural with age, but the maximum difference may be 

 taken at i p.ct. on the wood, or approximately 10 p.ct. on the 

 furfural-yielding constituents themselves. 



In other specimens, on the other hand, a slight increase was 

 observed, thus : 



Juglans cinerea. 



Furfural 



r (I) 4-18 years old .... 9-1 p.ct 

 <(2) 8-9 



f(i) 60-65 > . ... 9*6 

 K2) .... 9'S 



Fraxinus ameritana. 



2-7 years old . ... .8*9 p.ct. 

 51-52 9'4 



