"Yes," he said, "we all felt the same way you do, when we took our first few trips. There used to be hot arguments as to whose turn it was at the port hole, and we had to arrange regular times between us. The novelty soon wore off, though, and now, as you see, there isn't much competition."
"Well, it's new to me, yet, and I certainly find it very interesting," replied Bert. "These fishes seem to be every color of the rainbow, and the way they keep darting in and out reminds me of a kaleidoscope on a large scale.
"It does, rather," the lieutenant assented, "and, believe me, we see lots of things besides fishes, too. Why, I've come across all kinds of wrecked ships, from rowboats to big four-mast-ers. In tropic waters, we've seen many a ship that I'm sure was an old Spanish galleon, and I'll wager there's many a fortune in gold and silver pieces that we've had to pass over in the performance of duty. There are uncounted riches lying at the bottom of this old ocean, my boy."
"I don't doubt it in the least," answered Bert, and then Mr. Warren went on to tell him various yarns of strange adventures he had undergone and marvelous things that he had seen. Bert listened, fascinated, for the officer was a man who had not only been all over the world, but knew how to tell a story. The time passed more quickly than he had dared to hope, and just before dawn, he was told that they were almost at the entrance of the Canal.
The little submarine flew into the great new waterway, and hesitated no more than the brave hearts guiding its course. Its powerful searchlight illuminated the Canal from side to side, and they were able to get an idea of the immensity of the completed enterprise. Mile after mile, the smooth concrete wall slipped away back of them, thick, ponderous, designed to last as long as civilization lasted, and perhaps longer. As Bert gazed, his heart thrilled with a great pride at what his country had accomplished, and this feeling was succeeded by a fierce hatred of those who were plotting to set the great work at naught.
But now, the submarine had almost reached the mined gate of the Lock, and its speed was gradually reduced three-fourths. It nosed cautiously along, until the searchlight revealed a vast structure directly ahead. Instantly the motors were reversed, and by the time the boat's speed had been checked, it was not more than thirty feet from the gate.
In the meantime one of the crew had been encased in a diver's suit and now made ready to leave. He was conducted into an air-tight room near the bottom of the submarine, and, after the door had been securely fastened, water was admitted. When the room was full, the diver opened a door in the hull and stepped out of the boat, which had previously been lowered until it rested on the Canal bottom.
From the porthole in the submarine's bow he could be seen slowly making his way, following the luminous path made by the searchlight. In a short time he reached the gate of the lock, and began to follow its course toward the bank. He was soon out of the range of vision of those at the porthole, but, in a few minutes, returned; and it could be seen, by the way in which he still scanned the walls, that he had not yet found the wires leading to the explosives.
He had traversed perhaps half the distance from the center to the other bank, when he was seen to stop suddenly and carefully examine something near the lock.
"I'll bet he's found the wires," exclaimed Bert, excitedly.