"Perhaps they'll just watch the house for a day or two," said Hugh. "It may be though that now that those Germans know they are watched they may meet in some other place."

"True enough. I wish we could find the place."

Presently they came to the spot where they had left their bicycles. They were still there, and a moment later the boys were wheeling them back across the field again. Once more in the road, they mounted and soon were riding towards home. Their minds were busy with plots and Germans and the recent experiences they had undergone. They felt sure that they were on the trail of a desperate gang, and that quick action perhaps was necessary to prevent untold damage, and possible loss of life.

They were confused, however. Everywhere they turned they seemed to run into some new angle of the affair, or some other person who might bear watching. Hugh was still of the opinion that Heinrich and Lena should be looked after pretty carefully, though Bob laughed at him. He knew his family felt that their servants could be relied upon absolutely. Bob wondered about his father's plant; was it properly guarded? Perhaps his father might consent to let him go down there and help watch over it at night.

Talking but little they spun along the road. Each boy was occupied with his own thoughts, and consequently did not notice an automobile rapidly approaching down the road.

"Here comes a car," exclaimed Bob suddenly. They swung over to the right side of the road to let it pass, and a moment later it roared past them in a cloud of dust.

"Bob," cried Hugh excitedly. "The gray roadster."

"I know it. Did you see who was in it?"

"I didn't notice."

"Mr. Wernberg."