Just as he reached the clearing which separated the dwelling from the woods, he stumbled and almost fell. His foot had caught against something which felt like the trunk of a fallen tree, but which moved with an ease entirely foreign to a log of that size. Puzzled, Marks waited until a cloud which had concealed the moon had drifted by, and then commenced his examination. Yes, it was a log--and a big one, still damp from its immersion in the river. But it was so light that he could lift it unaided and it rang to a rap from his knuckles. The end which he first examined was solid, but at the other end the log was a mere shell, not more than an inch of wood remaining inside the bark. It was not until he discovered a round plug of wood--a stopper, which fitted precisely into the open end of the log--that the solution of the whole mystery dawned upon him. The silk had been shipped across the border from Canada inside the trunks of trees, hollowed out for the purpose! Wrapping the bolts in oiled silk would keep them perfectly waterproof and the plan was so simple as to be impervious to detection, save by accident. Emboldened by his discovery, Marks slipped silently across the cleared space to the shadow of the house, and thence around to the side, where a few cautious cuts of his bowie knife opened a peep hole in the shutter which covered the window. Through this he saw what he had hoped for, yet feared to find--Petersen and three of his men packing bolts of white silk in boxes for reshipment. What was more, he caught snatches of their conversation which told him that another consignment of the smuggled goods was due from Trail, just across the border, within the week. Retreating as noiselessly as he had come, Marks made his way back to Northport, where he wrote two letters--or, rather, a letter and a note. The first, addressed to the sheriff, directed that personage to collect a posse and report to Ezra Marks, of the Customs Service, on the second day following. This was forwarded by special messenger, but Marks pocketed the note and slipped it cautiously under the door of the Petersen house the next evening. "It's a fifty-fifty split," he consoled his conscience. "The government gets the silk and the Petersens get their warning. I don't suppose I'll get anything but the devil for not landing them!" The next morning when the sheriff and his posse arrived they found, only an empty house, but in the main room were piled boxes containing no less than thirty thousand yards of white silk--valued at something over one hundred thousand dollars. On top of the boxes was an envelope addressed to Ezra Marks, Esq., and within it a note which read, "I don't know who you are, Mr. Customs Officer, but you're a man!" There was no signature, but the writing was distinctly feminine. * * * * * "And was that all Marks ever heard from her?" I asked, when Quinn paused.