"The last of these must have been near to a hit, for it brought up oil bubbles three feet in diameter, with smaller bubbles of air inside of them. The oil-slick left behind by his wake was so heavy that, even in the failing light, it was visible for several miles. He was now making about five knots. We followed that broad slick of oil for some time after darkness had fallen, and it was not till a little before midnight that we lost it. "There wasn't much hope of regaining touch before daybreak, but on the off-chance the captain started circling in a way that would cover a lot of sea, and yet not take us too far from the centre of interest. "It was a little after one in the morning that one of the look-outs--perhaps 'sniff-outs' would be a better term under the circumstances--reported an oil smell to windward. The captain promptly ordered her headed up into the wind, with sniffers stationed to port and starboard, fore and aft. Every man on watch was sniffing away on his own, of course, and you can bet it would have been a funny sight if there had only been enough light for us to see one another in. Nosing--I can use the term literally this time--slowly along, turning now to port, now to starboard, as the oil smell was strongest from this side or that, within ten minutes we picked up a slick which, even in the darkness, it was evident was trending to south'ard. For an hour and a half we zigzagged up along that wake, keeping touch by smell until just before three o'clock, when the new well-risen moon showed it up distinctly to the eye. No," answering my frivolous interruption, "I don't recall noticing at the time that it was a _blue_ moon. "Ten minutes later we came up to where the wake turned to south-westward, and had a brief glimpse of Fritz trying to evade detection by running down the moon-path. He was plainly near the end of his juice, and taking every chance that offered to charge on the surface. He ducked under before there was time for a shot, but, knowing that he could hardly stay there for long, we continued following down his wake. "It was broad daylight when, at half-past four, we sighted him again, running awash about five hundred yards ahead and slightly on the starboard bow. Ordering the bow gun to open fire, the captain put the _Sherill_ at full speed and headed in to ram. The shots fell very close, but no hit was observed. "He turned sharply to port, preparing to dive. We tried to follow with full left rudder, but missed by twenty feet. His conning-tower and two periscopes showed not over thirty feet from the port side as we swept by. It was too close for a torpedo, nor was there a fair chance for a depth-charge. The port battery was opening on him as he submerged.