“Come, Tom,” exclaimed the aged inventor impatiently, “we must start at once!”

“Won’t morning do as well, dad?”

“No, I must start now.  I could not sleep worrying over what has happened.  We will start—­”

At that instant there came a low, rumbling peal of thunder.  Mr. Swift started and peered from a window.  There came a flash of lightning and another vibrant report from the storm-charged clouds.

“There is your bill, Mr. Swift,” remarked the proprietor, coming up, “but I would not advise you to start to-night.  There is a bad storm in the west, and it will reach here in a few minutes.  Storms on Lake Carlopa, especially at this open and exposed end, are not to be despised, I assure you.”

“But I must get home!” insisted Tom’s father.

The lace curtain over the window blew almost straight out with a sudden breeze, and a flash of lightning so bright that it reflected even in the room where the incandescent electrics were glowing made several others jump.  Then came a mighty crash, and with that the flood-gates of the storm were opened, and the rain came down in torrents.  Tom actually breathed a sigh of relief.  The problem was solved for him.  It would be impossible to start to-night, and he was glad of it, much as he wanted to get on the trail of the thieves.

There was a scurrying on the part of the hotel attendants to close the windows, and the guests who had been enjoying the air out on the porches came running in.  With a rush, a roar and a muttering, as peal after peal of thunder sounded, the deluge continued.

“It’s a good thing we didn’t start,” observed Ned.

“I should say so,” agreed Tom.  “But we’ll get off the first thing in the morning, dad.”

Mr. Swift did not reply, but his nervous pacing to and fro in the hotel office showed how anxious he was to be at home again.  There was no help for it, however, and, after a time, finding that to think of reaching his house that night was out of the question, the inventor calmed down somewhat,

The storm continued nearly all night, as Tom could bear witness, for he did not sleep well, nor did his father.  And when he came down to breakfast in the morning Mr. Swift plainly showed the effects of the bad news.  His face was haggard and drawn and his eyes smarted and burned from lack of sleep.

“Well, Tom, we must start early,” he said nervously.  “I am glad it has cleared off.  Is the boat all ready?”

“Yes, and it’s a good thing it was under shelter last night or we’d have to bail it out now, and that would delay us.”

An hour later they were under way, having telephoned to the engineer at the Swift home that they were coming.  Garret Jackson reported over the wire that he had notified the Shopton police of the robbery, but that little could be done until the inventor arrived to give a description of the stolen articles.