"I was at the indicator when an officer went up and the hatch was raised. As he didn't push it all the way down I had an idea he might soon return, so I moved up and stood between the twin tanks to the right of the steps. When the officer raised the hatch a streak of sunlight went right across the under side at the corner of the door, and I knew it couldn't come in at the front port hole," said Ralph, with a glow of pleasure in the discovery.
The captain shook his head slowly, as he said: "I am afraid this will mean an additional source of worry to all of us; it is bad enough to be locked up and subjected to the guns of vessels and warships, but it will be doubly hazardous to pass through the mine fields, and avoid the nets."
"Do you know anything about them, and how and where they are located?" asked Alfred.
"Yes, I have a pretty good knowledge of their location, and how to avoid them, although they constantly change the nets, or provide new safety outlets," said the captain.
The Steel Nets[ToList]
"What do you mean by safety outlets?" asked Alfred.
"Immense steel nets are stretched across the straits from Calais to Dover, two lines, in fact, between which the vessels plying between England and France go to and fro in safety. Furthermore, war vessels guard these nets on both sides, so that it would be a difficult matter to get near the nets," said the captain.
"But submarines do seem to get through somewhere; do they not?" asked Ralph.