"Do you suppose they have a regular organization to blow up everything around here that they can?" said Hugh. "I should think the secret service would get after them." "Probably it has; no doubt the names of all those men are listed." "That is, if they really are plotters." "Of course. Where are you going!" They had kept straight on down the road and were now on the outskirts of the city. The houses were fewer and more scattered all the time and presently the boys would be in the open country. "I don't know," said Bob. "I was just going ahead without thinking." "We'd better go back, hadn't we? We must be about three miles from home." "There's a road up ahead here to the right," said Bob. "We can turn down there and go back that way." When they were about two hundred yards distant from the road in question, an automobile came out of it and turned into the main highway. A moment later it was speeding along in front of Bob and Hugh, the roar of its cutout coming faintly to their ears. "Bob," exclaimed Hugh excitedly, "that's the gray roadster!" "What gray roadster?" "The one we passed in front of your house. It came from the Wernbergs'." "Shall we follow it?" "Certainly. It's going like the wind though." "Well, it can't lose us," said Bob grimly. He advanced the spark, gave the motor more gas and they were soon tearing through the night at fifty miles an hour. Over the crest of a hill in front of them, the gray roadster was outlined for a moment and then disappeared. Up the grade of the hill Bob drove the big car. When they arrived at the top they peered ahead anxiously for any sign of the machine they followed. Nothing was to be seen of it. "It's gone," exclaimed Hugh. "Perhaps not," said Bob. "It can't be very far ahead of us anyway." They continued down the road at breakneck speed, passing through a clump of woods that lined both sides. Bob forced the motor to its utmost, but no sign of the gray roadster could they discover. Finally he brought the car to a dead stop and turned to Hugh. "What became of that car?" he demanded. "They weren't far enough ahead of us to have gotten out of sight so quickly." "They must have turned off into another road," said Hugh. "I don't see what else could have happened." "But there are no roads into which they could have turned." "Are you sure?" "Positively." Both boys relapsed into silence, completely mystified by the strangeness of the thing. Apparently the roadster had vanished from the face of the earth. "Wait a minute," cried Bob suddenly. "There is a road back there too." "I thought there must be." "Remember those woods back there, just this side of the hill?" "Yes. That's where we used to go for chestnuts in the fall." "That's the place. Remember the old house back in there?" "It's deserted and tumble-down." "I know it, but there's an old wagon road leading to it." "Do you think that is where they went?" exclaimed Hugh in surprise. "Where else could they have gone?"