The lieutenant bounded into the conning tower, anxious to have the honor of giving the first signal. Seizing the lever of the telegraph, he signaled below to the anxious engine room force:
“Go ahead. Slow!”
Lockyer’s eyes burned, and his lips were so dry that he was compelled to moisten them as he gave the lever a shove. Instantly a tremor shot through the drifting little vessel. At the same moment a bright flash of metal shone in the engine room, as the light gleamed on the first revolution of the crank shaft.
“Head out of the harbor, Strong!” ordered the lieutenant, gripping Ned’s shoulder, as he stood behind him. Ned spun the spokes over, and the Lockyer obediently swung round. Then, with her engines purring as sweetly as a dozing cat’s lullaby, the submarine slipped noiselessly out of Grayport.
Coming forward into the cabin, the inventor turned a switch which controlled the red and green lights on either side of the bow. It was necessary to have these on, as big steamers, crowded with passengers for Boston, run up the Sound at night. Besides, the waters are usually pretty well dotted with sailing craft and small coasting steamers.
“Come ahead on your speed now,” whispered the inventor, slipping up the steel stairway into the darkened conning-tower. Under the starlight the broad Sound, gently heaving, lay before them. Ned’s hand slid to the telegraph. In instant response to the signal, the triple screws of the Lockyer began to churn the water faster.
“Fifteen knots!” exclaimed the inventor, gazing at the speed indicator, which was illuminated by a hooded light, “and we haven’t begun to go yet. Wait till that engine gets limbered up.”
“Keep her east and a little north,” ordered the officer, peering into the binnacle, “we’ll pick up the light on that course.”
Forward forged the Lockyer with hardly a vibration. So easily did she ride, in fact, that it was difficult to realize the speed at which they were proceeding. Lockyer, his face aglow, kept running up and down the ladder between the engine room and the conning-tower.
“We’ve cut off the gas now,” he said when he returned from one of these errands; “we are now proceeding under compressed air alone.”