"The meshes of the nets are very large,—that is, of sufficient diameters to permit the ends of the submarines to pass into them," replied the captain.
"But, if that is the case why cannot the submarines back out in the same way that they went in?"
"They can, if the mesh is too small to take more than the bow of the vessel; but, in the event the mesh is large enough to permit the bow to enter, and the net once gets behind the fins of the submarine, that is the end of them, for the vessel cannot, in that case, free itself," responded the captain.
"How was it in our case?" asked Ralph. "Do you think the fins of our ship got caught?"
"I did not explain it to you at the time, as I did not wish to alarm you; but this vessel had one of its fins through the net. Evidently we struck the nets at an angle, and the tide helped us in keeping the hull against the net at the proper angle. The lieutenant knew this, for he adopted the only method known to free the ship under those circumstances," said the captain.
"So you think the lieutenant knew that only one fin had caught, and for that reason he tried to up-end the ship?" inquired Alfred.
"Yes; but not that alone. I observed one thing that you may have overlooked," remarked the Captain. "He was particular to store all the boxes which we helped to carry aft, on the starboard side."
"I noticed that," said Ralph hurriedly, "and that wasn't all. Every time a box was brought in he would ask: 'Heavy or light,' and I have many times wondered why he did so."
"I did notice one thing, though," said Alfred, "and that was, when the rear end of the submarine shot upward, and the boxes came tumbling down, that the hull seemed to roll around to the left."
"That was our salvation," replied the captain. "I then knew we had a chance."