As Tom Swift and Mary Nestor approached the blaze—for blaze it was, since they could now notice a redness that betokened flames—they could see it more plainly, and a sense of relief came to the young man when he noted that it was in a spot remote from his shops. “Guess it’s a forest fire, Mary,” Tom observed. “I thought one would break out soon, it’s been so dry.” “I’ve never seen a forest fire,” she responded. “It must be very thrilling.” “It is—and dangerous,” replied Tom. “Well, you’re going to see one now, for we’re going right over it.” “Do you think it will be safe, Tom?” “Why not? We’re so high you won’t even smell the smoke. And as for the heat—well, they do get pretty warm, but you won’t feel that.” “Oh, I didn’t mean that so much,” Mary hastened to say. “But if anything should happen to the plane——” “Nothing is going to happen!” laughed Tom. “I’m going to give you a real view of a forest fire.” The smoke was rolling up in great clouds now. But of course the _Hummer_ was far above the conflagration. Nor could they hear the crackling of flames, though this sound was audible to those fighting the fire. Men and boys were at work combating the forest fire. Tom and Mary, from their vantage point high in the air, could note figures, like ants or flies, hastening from the surrounding country toward the scene of the blaze. Some were hastening up in autos, and others in horse-drawn vehicles. “What do they do when they fight forest fires?” asked Mary. “I don’t see any engines.” “Engines aren’t of much use—the fire is very seldom near a water supply,” answered Tom. “The only thing to do is to take away the stuff a fire feeds on—dry leaves, sticks, wood or anything else. Sometimes they do this by digging up the ground or plowing it in broad, bare strips. “Another way is to make a back fire. That is, they start some distance off from the blaze and set fire to a limited area. When this burns off, and of course it has to be kept under control, it leaves a black space with no fuel for the fire to feed upon, and when the original fire gets to the place it just naturally quits. They use wet bags, pieces of carpet, anything to beat out the line of flames when they actually fight the fire.” “It must be hard work,” decided Mary. “It is—hot, hard, dirty work. Well, we’ve got a pretty good view of this fire now, and I must say I don’t like the looks of it,” remarked Tom. They were fairly over the burning area now. Below them were the snapping, leaping flames and the billowing clouds of smoke. More men and boys were hastening up to do what they could to combat the conflagration. “If there should only come a rain now it would settle the fate of this fire,” remarked the young inventor. Tom looked up and across the sky. It was blue in nearly every quarter—too blue and beautiful to suit those who wanted water to pour down from the heavens.