And the weigher, pausing only to secure his coat, left the vault.
"Why all the stage setting?" inquired Preston. "You don't suspect...."
"I don't suspect a thing," Drummond smiled, searching for his own coat, "beyond the fact that the solution to the mystery is so simple as to be almost absurd. By the way, have you noticed those scratches on the bars of the grille, about four feet from the floor?"
"No, I hadn't," admitted the director. "But what of them? These vaults aren't new, you know, and I dare say you'd find similar marks on the grille bars in any of the others."
"I hope not," Drummond replied, grimly, "for that would almost certainly mean a shortage of gold in other sections of the Mint. Incidentally, has all the rest of the gold been weighed?"
"Every ounce of it."
"Nothing missing?"
"Outside of the seven hundred pounds from this vault, not a particle."
"Good—then I'll be willing to lay a small wager that you can't find the duplicates of these scratches anywhere else in the Mint." And Drummond smiled at the director's perplexity.
When the men arrived with a truck loaded with gold bars, they stacked them—at the superintendent's direction—along the side of the grille nearest the vault entrance.