"Exactly—but the grille door was sealed with the official governmental stamp when we entered the vault yesterday. That stamp is applied only in the presence of both men who know the combination. So the conspiracy, if there be any, must have included Cochrane, Strubel, and Jamison—instead of being a two-man job."
"How much gold did you say was missing?" inquired the Treasury operative, taking another tack.
"Seven hundred pounds—fifty bars of fourteen pounds each," answered Bosbyshell. "That's another problem that defies explanation. How could one man carry away all that gold without being seen? He'd need a dray to cart it off, and we're very careful about what goes out of the Mint. There's a guard at the front door all the time, and no one is allowed to leave with a package of any kind until it has been examined and passed."
A grunt was Drummond's only comment—and those who knew the Secret Service man best would have interpreted the sound to mean studious digestion of facts, rather than admission of even temporary defeat.
It was one of the government detective's pet theories that every crime, no matter how puzzling, could be solved by application of common-sense principles and the rules of logic. "The criminal with brains," he was fond of saying, "will deliberately try to throw you off the scent. Then you've got to take your time and separate the wheat from the chaff—the false leads from the true. But the man who commits a crime on the spur of the moment—or who flatters himself that he hasn't left a single clue behind—is the one who's easy to catch. The cleverest crook in the world can't enter a room without leaving his visiting card in some way or other. It's up to you to find that card and read the name on it. And common sense is the best reading glass."
Requesting that his mission be kept secret, Drummond said that he would like to examine Vault No. Six.
"Let Cochrane open the vault for me and then have Jamison and Strubel open the grille," he directed.
"Unless Mr. Bosbyshell opened the vault door," Preston reminded him, "there's no one but Cochrane who could do it. It won't be necessary, however, to have either of the others open the grille—the door was taken from its hinges this morning in order the better to examine the place and it hasn't yet been replaced."
"All right," agreed Drummond. "Let's have Cochrane work the outer combination, then. I'll have a look at the other two later."
Accompanied by the director and the superintendent, Drummond made his way to the basement where they were joined by the official weigher, a man well over fifty, who was introduced by Preston to "Mr. Drummond, a visitor who is desirous of seeing the vaults."