But the wily Celestial baffled all efforts to "pump" him, and the matter passed from their minds.
Two days later, however, Wah Lee shuffled past Bert, as the latter was sauntering down the main street of Colon, and, apparently by accident, touched his arm in passing. Bert looked up, and, recognizing the Chinaman, started to speak to him. But the latter only gave him a swift glance from his almond eyes, and kept on, his face as stolid and inscrutable as that of a graven image. In that fleeting look, however, Bert's quick perception recognized that Wah Lee had some object in view, and wanted to talk with him. With a heightened pulse, but still retaining an indifferent air, he followed.
At the first turning, the Chinaman passed into a side street, Bert keeping a little way in the rear. The houses grew more infrequent and soon they came to the suburbs. Still on they went, until, at last, they were in the open country, and free from observation. Then, in a remote spot, where they could see for a long distance on every side, Wah Lee stood still, and Bert ranged alongside.
"Well, Wah Lee," he asked, curiously, "what's the game?"
In answer, the Chinaman drew from his pocket a crumpled sheet of paper, and handed it to Bert. He took it and smoothed it out. At first, it failed to convey any impression. The drawing was a rough one, and seemed to consist of a series of lines, punctured with dots. But gradually, as Bert gazed, his training in mechanics told him that it was a plan of some large structure. There were two rectangular outlines, that were perfectly similar, like two leaves of a table. No, they were gates. And then, like a flash, it came across him. They were the gates of the Gatun Locks! There was the wavy line, to indicate the water level, and, down below these, were the ominous dots. They seemed to be meant for holes, but his knowledge of the locks told him that they had no place in its structure. What did those holes mean?
A little shaken, he looked at Wah Lee for the key to the enigma.
"Where did you get this?" he asked.
"Found it," answered the Chinaman. "Man drop it. Man come to see my bloss. My bloss kill clanal," Wah Lee repeated.
For a moment, Bert's head swam, and a thousand bells seemed to ring in his ears. Then he steadied himself, and plied the Chinaman with eager questions that sought to pluck the heart out of the mystery. Wah Lee's knowledge of English was very limited, and it took a long time and infinite patience to get from him what he knew. Gradually, he pieced the bits together, until the whole thing became clear and coherent in his mind.
By the merest accident, Wah Lee had heard enough to know that the Japanese who employed him was engaged in a plot to destroy the Canal. How or when it was to be done, he did not know. It was doubtful if he could have grasped the details, even if he had heard them, so full they were of technical matters that conveyed to him no meaning. But he knew that the plot existed, and dimly understood that this would bring pain and suffering to Bert. As far as he himself was concerned, a dozen canals might be destroyed, without affecting him in the least. But he held the boys in strong affection for having saved his life, and he knew that he could pay his debt, at least in part, by letting them know what was brewing.