"The arts of fire building are not so simple as they look. To practice them successfully in all sorts of wild regions we must know the different species of trees one from another, and their relative fuel values, which as we shall see, vary a great deal. We must know how well, or ill, each of them burns in a green state, as well as when seasoned. It is important to discriminate between wood that makes lasting coals and such as soon dies down to ashes. Some kinds of wood pop violently when burning and cast out embers that may burn holes in tents and bedding or set the neighborhood afire; others burn quietly, with clear, steady flame. Some are stubborn to split, others almost fall apart under the axe. In wet weather it takes a practiced woodsman to find tinder and dry wood, and to select a natural shelter where fire can be kept going during a storm or rain or snow, when a fire is most needed. "There are several handy little manuals by which one who has no botanical knowledge can soon learn how to identify the different species of trees by merely examining their leaves, or, late in the season, by their bark, buds and habit of growth. "But no book gives the other information that I have referred to; so I shall offer, in the present chapter, a little rudimentary instruction in this important branch of woodcraft. "It is convenient for our purpose to divide the trees into two great groups, hard woods and soft woods, using these terms not so loosely as lumbermen do, but drawing the line between sycamore, yellow birch, yellow pine, and slippery elm, on the one side, and red cedar, sassafras, pitch pine and white birch, on the other. "_As a general rule_, hard woods make good, slow-burning fuel that yields lasting coals, and soft woods make a quick, hot fire that is soon spent. But each species has peculiarities that deserve close attention. "_Best Fuel_--Best of all northern fire woods is hickory, green or dry. It makes a hot fire, but lasts a long time, burning down to a bed of hard coals that keep up an even, generous heat for hours. Hickory, by the way, is distinctly an American tree; no other region on earth produces it. The live oak of the south is most excellent fuel; so is holly. Following the hickory, in fuel value, are chestnut, oak, overcup, white, blackjack, post and basket oaks, pecan, the hornbeams (ironwoods), and dogwood. The latter burns finely to a beautiful white ash that is characteristic; apple wood does the same. Black birch also ranks here; it has the advantage of 'doing its own blowing,' as a Carolina mountaineer said to me, meaning that the oil in the birch assists its combustion so that the wood needs no coaxing. All of the birches are good fuel, ranking in about this order: Black, yellow, red, paper, and white. Sugar maple was the favorite fuel of our old-time hunters and surveyors because it ignites easily, burns with a clear, steady flame, and leaves good coals.