“Pass the word for slow speed, Mr. Dalzell,” Dave commanded, quietly. “We want to keep behind that craft for a moment. Pass word to Mr. Briggs to stand by ready to drop a depth bomb.”
Quietly as the orders were given, they were executed with lightning speed. The destroyer began to move more slowly, keeping well behind the bubble trail. At any instant, however, the “Logan” could be expected to leap forward, dropping the depth bomb at just the right moment. Then would come a muffled explosion, and, if the bomb were rightly placed, a broad coating of oil would appear upon the surface.
Dave was now in the very peak of the bow. Watching the bubbly trail he knew that the hidden enemy craft was moving more slowly than the destroyer, and he signalled for bare headway. And now the bubbles were rising as though from a stationary object under the waves.
“Buoy, there!” he ordered, quickly. “Overboard with it.”
Slowly the destroyer moved past the spot, but the weighted, bobbing buoy marked the spot plainly.
“Have a diver ready, Mr. Dalzell,” Dave called. “Make ready to clear away a launch!”
In the matter of effective speed Darrin’s officers and crew had been trained to the last word. Only a few hundred yards did the “Logan” move indolently along, then lay to.
Soon after that the diver and launch were ready. Dave stepped into the launch to take command himself.
“May I go, too, sir?” asked Dan Dalzell, saluting. “I haven’t seen this done before.”
“Clear away a second launch, Mr. Dalzell. The crew will be armed. You will take also a corporal and squad of marines.”