YULE FIRES 347 



black maples are not far behind in value. Our 

 American white ash and elm rank well up with 

 the oaks, so does beech, while the softer woods 

 fall behind. Moreover, trees grown on high, 

 droughty, barren soil show greater heating power 

 than those of the same variety which happen to 

 stand in rich, but moister soil. 



Long ago an American chemist confirmed what 

 the practical experience of the woodman had al- 

 ready decided. Marcus Bull's table of the heat- 

 ing value of American woods is as follows: 

 Shagbark hickory, 100; white oak, 81 ; red oak, 

 68 ; sugar maple, 60 ; red maple, 54 ; white ash, 

 yj; chestnut, 52; white beech, 65; black birch, 63; 

 white birch, 48; pitch pine, 43; white pine, 42. 



Wood, according to the chemists, is a carbo- 

 hydrate and the greater the proportion of carbon 

 which it contains the greater is its heat-giving 

 value, the greater the proportion of hydrogen 

 the greater the output of ruddy flames. Yet 

 chemists, who are so sure the alchemists had no 

 ground for their beliefs, do not always agree 

 among themselves. Professor Bull's table of the 

 heat-giving properties of the various woods has 

 been declared inaccurate by other chemists, in 

 spite of the fact that experience in actual use 



