The other boat gave no better results. Its sailors had seen nothing, and we ran back to the point whence the waves had come, for a brief consultation. As we gazed on the quiet water just tinged with the last of the sunset, I spoke.
“There’s only one explanation, if the wave-measuring machine is correct. He’s down on the bottom in a submarine, or he was there when he sent off those waves.”
“I’m afraid that’s right, Jim,” said Tom. “If I could only see down there. I wonder how deep it is.” He called to the captain. “Take a sounding here, will you please?”
We hurried forward and watched the line overboard. Fathom after fathom disappeared up to the very end. “It’s more than a hundred twenty fathom, sir,” reported the captain.
“No use, then,” said Tom. “Go right back to Folkestone. We’ll have a couple more tries to-morrow,” he went on. “But, frankly, I’m afraid it won’t do any good. To find a submarine in these waters would be worse than finding a needle in a haystack.”
It was a rather gloomy little party that landed at Folkestone that night. We had seemed so near success. Yet there was one alleviation. I had dreaded bringing Dorothy into danger, and I had had a most uneasy feeling as to the possible result of the meeting with a man inspired with so fixed and fearful a purpose as he whom we sought. Much as I desired the completion of my search, I could not therefore feel too complete a sense of regret at the two failures which we encountered on the Channel the next day. The man was in the Channel sea. He was experimenting with his apparatus daily under its waves. We could be sure of that, but he could not be reached, so we finally gave in and returned to London.
All the way up in the train, Dorothy sat in deep thought, but no result came from her meditations, and we returned to the Savoy without a ray of light as to our next move.
The next morning I woke with fresh courage. We had gained so much and so unexpectedly, that I felt convinced we must gain more. I found a table in the dining-room, and waited there for Tom and Dorothy, who shortly appeared. We breakfasted gaily. The morning sun shone brightly on the little park below the window and on the Thames, flowing slowly beyond. The peaceful scene looked little like war, but the papers before us were full of dire forebodings. The German Emperor still sulked. Movements of army corps and of battleships were the main part of their story. Despite the columns filled with martial things, every newspaper had at least one reference to the man who was trying to stop all war, and in more than one of them was a word as to the double danger of the fleets, who faced not only a foreign foe, but annihilation at the hands of this unseen destroyer. As we finished breakfast, Dorothy asked, “What are you boys going to do this morning?”