Admiral Fischer scanned it closely.
"It's authentic enough," he said finally, "I know his signature well. And this raid is to take place at midnight, eh?"
"Well, no. We are to gather at midnight. How long it will take to reach the mouth of the Thames you can figure yourself."
"I can," declared the admiral. "And I can also figure that if these submarines dare enter the Thames they will never get out."
"But you must figure better than that, Admiral. You must figure so they will be unable to do any damage. That's even better than figuring that they cannot escape after the damage is done."
"So it is," returned the admiral. "Have you a plan?"
"Why, yes! You must immediately order all warships and other craft now at the mouth of the Thames, further up river. Order a swift torpedo boat flotilla down the river—as many as are available—and have half a dozen torpedo boats—equipped with nets—to take their places behind the motorboat fleet."
"And then?"
"Well, the motorboats will attack the submarines as soon as they appear. A few of them undoubtedly will be sunk. Then let the rest retire. The submarines, submerged by this time, will travel forward a bit. At this point have the torpedo boats, with nets stretched, proceed down each side of the river. Of course, the torpedo boats must advance at the moment the motorboats flee."
"But I should think the Germans are too wary to be caught in a trap like that."