"Let's scrounge anything we can find that runs on gasoline or coal oil," said Al Miner. "If we act fast we ought to be able to pick up some old motorcycle engines or some power lawn mowers from the dump. Thompson's have probably got some. We can try people's basements, too. Let's get as many as possible, because we don't know how long any one will last, and we may have to run the blower for weeks, in order to get any kind of sample." "Good idea," said Ken. "Here's something else: Who's got a car left to gather this stuff in?" The boys looked at each other. "Ours was still running this morning," Frank Abrams said, "but I won't guarantee how long we can count on it." "Pretty soon there won't be any we can count on. We've got to get a horse and wagon before they start selling for as much as a new Cadillac used to." "My uncle's got one on his farm," said Dave Whitaker. "He would probably loan it to me, but he's five miles out of town." "Take my bike," said Ken. "See if he'll let you borrow it and a wagon for at least a couple of weeks or longer. Bring some bales of hay, too." "Right now?" "Right now." When Dave had gone, Al said, "What about the blower? Anybody know where we can get one of those?" "I think there's one at Thompson's," said Ted. "They pulled it out of Pete and Mary's restaurant when they remodeled." "That would be just a little kitchen blower. Not big enough--we need a man-sized one." Ken said, after a long pause, "There isn't one in town. The chances of getting one from somewhere else are practically zero. Frederick is 50 miles away and by tomorrow there may not be a car in town that would go that far." "Look," said Al, "how about the air-conditioning systems in town? There isn't one that's any good where it is, now. Both the high school and the college have big ones. I'll bet we could get permission at either place to revamp the intake and outlet ducts so we could put in our filters and precipitators. Your father and his friends could swing it for us at the college." "You might be right! It's worth trying. For precipitators we can rig a battery-powered system that will put a few thousand volts on the screens. Art will let us have enough car batteries for that. I think we're set!" * * * * * Dave Whitaker did not return until dusk, but he had succeeded in getting the horse and wagon, and a load of hay. He deposited this in his own yard before driving back to Ken's place. During the next two or three hours the boys found two old motorcycle engines, a power lawn-mower motor, and one old gasoline-powered washing machine. All of these they took down to Art Matthews' place and begged him for space and tools to overhaul the equipment. "You can have the whole joint," Art said dejectedly. "This pile of junk will never move!" He waved a hand at the cars lined up and down both sides of the streets near his place.