82 



NATURAL HISTORY OF THE FARM 



standing, needing cutting. Fire was the cutting agent first 

 employed. Trees were burned down by building fires about 

 their bases, and then by similar process they were cut in 

 sections. It was only for long-keeping fires that such fuel 

 was needed: there was always excess of kindling-stuffs 

 available for making quick fires. 



All wood will burn and give forth heat, but one who knows 

 woods will not use all kinds: it is only the degenerate 



FIG. 43. Western yellow pine dismantled and ignited by lightning (U. S. 

 Bureau of Forestry). 



modern, who will do that who will go to the telephone and 

 order a cord of wood without further specifications. Heavy, 

 close-grained, hard woods as a rule burn more slowly and 

 yield more heat than the lighter, more open-textured soft 

 woods. Combustible resins vary the rate of burning, and the 

 amount of heat produced : but the greatest differences in 

 burning qualities are due to the amount of water present. A 

 punky old log that when dry will burn like tinder, will soak up 

 water like a sponge and, becoming ''water-logged," will not 



