“No doubt about that and I think it also means that the trail is getting fairly warm.”
“If only we had not run up against them,” Jack sighed as he leaned back against a friendly spruce.
“I know,” Bob sympathized, “but what can’t be cured must be endured, you know.”
By four o’clock they had covered some five miles from where they had eaten their dinner. Three times during the afternoon they had heard the signal repeated. For the past two hours Bob had experienced a feeling that they were being followed. Several times, on turning his head, he had fancied that a bush had moved and once he was almost sure that he had caught a glimpse of a form as it dodged behind a tree some distance off to the right. He had said nothing to his brother as yet, but now, as they sat down for a short rest at the foot of a tall pine, he said:
“Jack, I’m pretty certain that we’re being shadowed.”
“I know it. That is I’ve thought so for an hour but didn’t say anything for fear you’d say I was seeing things again.”
“No danger of that,” Bob laughed. “Not after seeing that cabin or whatever it was. I’ll never accuse you of ‘seeing things’ again. You can bet your bottom dollar on that.”
So far they had seen no evidence of a trail or road leading over the border.
“They must take the stuff across either through the air or else through an underground passage,” Jack declared.
“Of course either one is possible especially the former but, you remember, the captain said that no air ship had been seen up here for some months, so it’s not very likely.”