"I understand that you are the only man who can open them," said the detective. "Suppose we look into this one," as he stopped, as if by accident, before Vault No. 6.
Cochrane, without a word, bent forward and commenced to twirl the combination. A few spins to the right, a few to the left, back to the right, to the left once more—and he pulled at the heavy door expectantly. But it failed to budge.
Again he bent over the combination, spinning it rapidly. Still the door refused to open.
"I'm afraid I'll have to ask you to help me with this, Superintendent," Cochrane said, finally. "It doesn't seem to work, somehow."
But, under Bosbyshell's manipulation, the door swung back almost instantly.
"Nothing wrong with the combination," commented Preston.
Drummond smiled. "Has the combination been changed recently?" he asked.
"Not for the past month," Bosbyshell replied. "We usually switch all of them six times a year, just as a general precaution—but this has been the same for the past few weeks. Ever since the fifteenth of last month, to be precise."
Inside the vault Drummond found that, as Preston had stated, the door to the grille had been taken from its hinges, to facilitate the work of the men who had weighed the gold, and had not been replaced.
"Where are the gold bars?" asked the detective. "The place looks like it had been well looted."