“Send that!” he said brusquely, shoving the despatch under the inquisitive operator’s nose. “I want the reply sent to Dexter Island the instant it comes.”

“Well, of all the idiocy,” he burst out angrily, after he had perused his father’s despatch once more. “For pure, unadulterated blunderers, commend me to these Canadian authorities. It’s all clear enough to me. They have been on the trail of diamond smugglers. I guess the authorities on both sides of the line have been cooperating. In some way that we don’t know, some of the operations of the gang have been traced to Dexter Island——”

“The Artful Dodger!” exclaimed Harry.

“Yes; perhaps they suspected that boat and traced her there, or heard of her being seen in that vicinity. Then when dad left hurriedly for Montreal I suppose they leaped at the conclusion that he must be one of the gang, and at once arrested him. Can you beat it?”

“You cannot,” said Percy Simmons with deep conviction; “you can’t even tie it.”

“What is to be done now?” asked Harry, with a note of despair in his voice.

Complications were surely piling up thick and fast for the Border Boys. Even in their most exciting times on the southern frontier, they had never encountered such a tangle of inexplicable happenings as that into which they now found themselves plunged.

“We’ll stick to the program I just outlined,” said Ralph. “It’s all we can do. If the authorities are on the lookout for the diamond smugglers, and if,—as we have every reason to suspect,—Hawke and Malvin are members of the gang, their arrest will be the first step in Dad’s exoneration.”

As there was nothing to be gained by lingering in Cardinal, the little party hastened down to the River Swallow. They found the lights burning, everything ship-shape, and Malvin and Hansen standing at the gangway ready to receive them. As Harry looked at Malvin’s respectful, courteous smile of greeting, he could not help repeating to himself a line from Hamlet that he had learned in school, to the effect that a man may “smile and smile but be a villain still.”

Acting under Ralph’s instructions, not one of the boys gave the faintest sign that they suspected anything. Ralph addressed some perfunctory inquiries and orders to Malvin, and then told him that he could cast off as soon as he got the order. It came as soon as Percy Simmons hailed the young skipper through the speaking tube, and told him that everything was all right below in the engine room.