But Tom and the others labored to such good advantage that in three days they had repaired most of the damage done. Luckily the vandal had cut and slashed in a hurry, and his malicious work was only half accomplished. There was no clue to his identity.
No trace was seen of the Fogers, and Tom hardly expected it, for he thought they were in Sitka by this time. Nor were any suspicious persons seen hanging around the shed. The adventurers left their rooms at the hotel, and took up their quarters in the airship that would soon be their home for many days. They wanted to be where they could watch the craft, and two guards were engaged.
"We'll start to-morrow," Tom announced gaily one evening when, after a hard day's work the last of the damaged planes had been repaired.
"Start fer th' valley of gold?" asked the miner.
"Yes. Everything is in good shape now. I want to go into town, to send some messages home, telling dad we'll soon be on our way, and I also want to get a few things."
"Shall I come?" asked Ned.
"No, I'd rather you'd stay here," spoke Tom, in a low voice. "We can't take any more chances of being delayed, and, as it's pretty well known that we'll sail to-morrow, the Foger crowd may try some more of their tricks. No, I'll go to town alone, Ned. I'll soon be back, however. You stay here."
But Tom came nearly never coming back. As he was returning from sending the messages, and purchasing a few things he needed for the trip, he passed through a dark street. He was walking along, thinking of what the future might hold for him and his companions, after they reached the caves of ice, when, just as he got to a high board fence, surrounding some vacant lots, he heard some one whisper hoarsely:
"Here he comes!"
The young inventor was on his guard instantly. He jumped back to avoid a moving shadow, but was too late. Something struck him on the back of his head, and he felt his senses leaving him. He struggled against the feeling, and he realized, even in that exciting moment, that the thick collar of his heavy overcoat, which he had turned up because of a cold wind, had, perhaps, saved him from a broken skull.