"As you know from sad experience, some green woods will not burn," began the guide. "Leaving aside the woods that will not burn, I'll mention some of those that will do good service when green. Hickory is the best of all. It makes a hot fire, lasts a long time, and burns down to a bed of coals that will keep up an even heat for hours. Next in value are the chestnut, oak and dogwood. Black birch is excellent, too, doing its own blowing."
"Blowing?" questioned the Professor.
"Yes, sir. That means that the oil in the birch assists its combustion, so that the wood needs no coaxing to make it burn. Sugar maple is good, too, but it is too valuable a tree to waste. Locust and mulberry are good fuel. Now white ash makes one of the first-class campfire fuels. It is easy to cut and tote and catches fire readily."
"What about kindling?" interjected Tad.
"Yes, kindling," urged Stacy. "I've burned up half of my old shirts trying to start fires."
"The birch bark is one of the best," answered the guide. "Besides, it makes good torches. It is full of resinous oil, blazes up at once, will burn in any wind, and even wet sticks may be kindled with it."
"That's new," nodded Butler.
"Stacy, there's your job. You won't have to sacrifice any more shirts in trying to start a campfire," said Ned. "Your job, from now on, is peeling birch bark for kindling."
"Pitch pine, of course, affords the best knots," continued Cale. "Splits from a stump whose outside has been burned are rich in resin. Don't pick up sticks from the ground, but rather those from the down wood. Ordinarily you will find fine dry wood in a tree that has been shivered by lightning."
"Br-r-r!" shivered the fat boy.