"Rather a fortunate accident, too," went on the invalid. "My nerves are much calmer now. I really think I shall be able to go to sleep. I must have taken the right kind of a current without knowing it. I'll do it the next time I find myself too wakeful."
"Please excuse us from helping," begged Frank, with a smile. "It's a little too much."
"Oh, no, I wouldn't think of shocking you again," said Mr. Ackerman as he began to take the battery apart for packing. "I shall take the current alone. But there, I must not talk or I shall be awake again. I must hurry and get to sleep."
"Isn't he the limit!" exclaimed Fenn, when he and Frank were back in the stateroom again. "He thinks that was fun for us."
The electrical treatment appeared to improve the sick man, for, the next day he was much better, and even laughed and joked about the night's experience.
The _Modoc_ continued on her course, putting many knots behind her, and the boys were more and more delighted with their cruise, which every day revealed to them new beauties of scenery.
One afternoon, when they were within a day's travel of Duluth, Captain Wiggs, who was sitting on deck with the four chums, arose suddenly and began to sniff the air.
"What's the matter? Is the cook burning the steak?" asked Fenn.
"Something's burning," answered the commander, with a grave face.
A moment later a sailor, much excited, came rushing up on deck.
"Fire in the forward hold, sir!" he called.
Captain Wiggs was not built on speed lines. He was short and squatty, and inclined to be fat. But the way in which he hustled about as soon as he heard what the sailor said was sufficient to qualify him to enter a go-as-you-please race of almost any kind.
With a few jumps he was at the companionway leading below, and, as he went the boys could hear him call out:
"Ring the fire alarm! Every man to his station! Someone tell the pilot to slow down! Signal to the engineer to get the pumps in gear!"
Nor were the members of the crew slow to carry out the commander's instructions. One man rang the automatic fire alarm, that sounded in every part of the vessel. Another hurried to the bridge, where he delivered the message about stopping the boat. The _Modoc_ at once began to lose way and, a moment later, the vibration from the engine room told the boys that the pumps had been started.