"Go ahead!" the captain of the gunboat, Frederick Curtis, said.

"George," he added, addressing an officer, "go to the boat and train her guns on this delightful party."

Carstens turned deadly pale but smiled, and saluted.

"I'm sure you will do nothing rash," he said.

"I shall not overstep my instructions," was the reply. "What have you to say?" he continued, facing Ned.

"I want a few words with you in private," was the reply.

"I protest!" shouted the Lieutenant.

"Best speak here," was the decision of the captain.

At this moment the senator's son made his appearance on the Tusk with a steel box under his arm. He advanced quickly to the group and pa.s.sed the box to Lieutenant Carstens.

"First," Ned began, "I ask you, Captain Curtis, to take charge of the box just given to Lieutenant Carstens."

Captain Curtis extended his hand for the box, but the Lieutenant drew back.

"This is unusual," the lieutenant said, "irregular and discourteous."

"I waive the point for the present," Captain Curtis said, "but I insist that the box shall not leave your hands until it pa.s.ses into mine."

"Next," Ned went on, encouraged by the words and manner of Captain Curtis, "I want you to have the cabin of the _Clara_ searched."

Lieutenant Carstens approached the speaker in a threatening manner, but Curtis stepped in front of him.

"Why shouldn't the cabin of the _Clara_ be searched?" the latter demanded.

"You shall pay for this indignity!" Carstens roared, turning away from the group, with the box still under his arm. Ned pointed to the box, and Captain Curtis stopped him.

"I want that box," he said, calmly.

Lieutenant Carstens hastened his steps and lifted the steel box in his hands, as if about to toss it into the sea. Before he could execute his purpose, however, the box was seized by the Captain.

"If you wish to a.s.sist in the search of the cabin," Captain Curtis said, "we will go there together. Come along, Nestor," he added, turning to Ned and cutting the cord which held his wrists. "You suggested the move, and you shall see what is discovered in the search."

The Lieutenant moved along with the others, but paused at the head of the stairway leading down into the little stern cabin.

"I protest against this!" he roared, his face bloodless with pa.s.sion or fright.

"By the way," Captain Curtis said, lifting the steel box high in the air, "this appears to be quite heavy. Suppose we open it here?"

"There is no key," Carstens replied.

Ned held up the odd-shaped key he had found on the island first visited.

"I think I can open it," he said, "but you'll find that Carstens has a key if you'll take a look through his clothes."

"Will you surrender the key?" asked Captain Curtis of the Lieutenant.

"The boy lies!" thundered Carstens. "I have no key."

"What does the box contain?" asked the Captain.

"I don't exactly know," Ned replied, "but it is my opinion that it contains a treaty pledging certain tribes to unite in rebellion against the United States provided they are supplied with guns and ammunition."

"Your opinion is of little account!" gritted the Lieutenant.

"And I believe," Ned went on, "that other papers are in the box--papers giving a history of the plot, also papers stolen from the government.

Anyway, if you say so, Captain, I'll open the box with my key and we'll soon find out."

"Perhaps we would better retire to the cabin," suggested Captain Curtis, noting the curious faces gathering about. "We can settle the whole matter there."

Lieutenant Carstens would not have entered the cabin if one of the officers of the gunboat had not crowded him down the stairway.

"This is an outrage!" he shouted.

The senator's son now came hastily down the steps, his face red with rage, his fingers working convulsively, as if already playing about the throat of an enemy.

"That box is mine!" he cried. "I demand that it be returned to me unopened. I am the son of a United States senator."

"If what I suspect is true," Ned said, "you will need all the political pull a member of the senate has in order to keep yourself out of the penitentiary."

"Put that boy out of this cabin!" snarled the young man. "This is my private room. I paid for its use during the cruise."

Ned whispered a few words to the Captain, and the latter turned with a smile to a door opening at the rear of the little room where the excited group stood.

"Well," he said, "there is a question here as to whether the box contains any treasonable doc.u.ments. If the box belongs to you, open it and we'll see if the charge is true or false. If it is false the box shall be returned to you."

"I have lost my key," was the reply.

"How long ago?" asked Ned.

The young man turned a supercilious face on the boy, but answered:

"Several days ago. What is it to you?"

"Where were you when you first missed it?" Ned persisted.

"That does not concern you," was the reply.

"If you lost it in Captain G.o.dwin's station," Ned said, with a smile, "I presume I have it."

He held up the key he had found on the river bank, among the bushes, on the morning following the abduction of Lieutenant Rowe, and the other lunged for it.

"Never mind!" Ned laughed, dodging away, "I don't care to part with the key just now. After the investigation of the box is over you may have it."