"The U-boat was there, all right. But so were four hydroplanes and half a dozen destroyers, all carrying the Stars and Stripes!" II THE MINT MYSTERY "Mr Drummond! Wire for Mr. Drummond! Mr. Drummond, please!" It was the monotonous, oft-repeated call of a Western Union boy--according to my friend Bill Quinn, formerly of the United States Secret Service--that really was responsible for solving the mystery which surrounded the disappearance of $130,000 in gold from the Philadelphia Mint. "The boy himself didn't have a thing to do with the gold or the finding of it," admitted Quinn, "but his persistence was responsible for locating Drummond, of the Secret Service, just as he was about to start on a well-earned vacation in the Maine woods. Uncle Sam's sleuths don't get any too much time off, you know, and a month or so in a part of the world where they don't know anything about international intrigues and don't care about counterfeiting is a blessing not to be despised. "That's the reason the boy had to be persistent when he was paging Drummond. "The operative had a hunch that it was a summons to another case and he was dog tired. But the boy kept singing out the name through the train and finally landed his man, thus being indirectly responsible for the solution of a mystery that might have remained unsolved for weeks--and incidentally saved the government nearly every cent of the one hundred and thirty thousand dollars." * * * * * When Drummond opened the telegram [continued Quinn] he found that it was a summons to Philadelphia, signed by Hamlin, Assistant Secretary of the Treasury. "Preston needs you at once. Extremely important," read the wire--and, as Drummond was fully aware that Preston was Director of the United States Mint, it didn't take much deduction to figure that something had gone wrong in the big building on Spring Garden Street where a large part of the country's money is coined. But even the lure of the chase--something you read a lot about in detective stories, but find too seldom in the real hard work of tracing criminals--did not offset Drummond's disappointment in having to defer his vacation. Grumbling, he gathered his bags and cut across New York to the Pennsylvania Station, where he was fortunate enough to be able to make a train on the point of leaving for Philadelphia. At the Mint he found Director Preston and Superintendent Bosbyshell awaiting him. "Mr. Hamlin wired that he had instructed you to come up at once," said the director. "But we had hardly hoped that you could make it so soon." "Wire reached me on board a train that would have pulled out of Grand Central Station in another three minutes," growled Drummond. "I was on my way to Maine to forget all about work for a month. But," and his face broke into a smile, "since they did find me, what's the trouble?"