A slight noise outside made the boy sit up erect and listen intently. He went to the door and looked out. There was nothing out of the ordinary there.
“I must be nervous to-night,� said Jack to himself, in tones of self-reproof. “What’s the matter with me? First I think I see a man and then I think I hear someone snooping about. Guess this climate doesn’t agree with me.�
But Jack was not, as he indignantly assured himself, the victim of nerves. There was a man outside his cabin. A man who was watching him eagerly through a port-hole opening into the wireless room. The man had a yellow, evil face and two glittering black eyes like a snake’s. In his ears hung two hoops of gold. It was Alvarez, the Spanish sailor.
He was there to witness the culmination of a plot he had formed that was to imperil Jack’s life.
While Jack was in the town, the man had sneaked on board with the agility of a monkey, swarming up one of the mooring lines, unnoticed. He had made his way at once to the wireless room. Once inside, from his pocket he had produced wires and pliers.
For half an hour or more he worked feverishly and with a skill in handling his tools that showed he was an expert mechanician. Indeed, the man had once been a skilled electrician, but a crime he had committed had forced him to flee his country and leave his employment and become a common sailor.
Every now and then, as he worked, he would stop and tip-toe to the door of the wireless room. He had no wish to be caught napping for he knew the power of Jack’s fist and the heavy penalty that would be visited upon him were he caught in the fiendish work upon which he was engaged.
Tirelessly he connected wires to terminals and finally he produced from his pocket an oblong black object formed, apparently, of metal. He connected wires to this and then, with a diabolical grin, planted it beneath the wireless table. He had completed his work just in time to dart from the cabin as Jack’s quick, firm step was heard ascending the companion ladder. So that the young wireless lad was not the victim of an illusion when he thought he saw a human figure.
Alvarez slipped in under a canvas boat cover while Jack was making a search. In his place of concealment he chuckled evilly to himself:
“Caramba! What a revenge is mine on this dog of a Yankee boy! Did he think that he could insult and beat a Spaniard without suffering? Todos los Santos, no! A few moments now and my revenge will be complete.�