Counterspy - The Case of the Captured Contact

A phone call is made to the Counterspy offices in Washington. The caller says "Mr. Harding? Mr. David Harding?" Harry says "No, this is Mr. Harding's assistant, Harry Peters". The caller says "I am calling from Baltimore. I must speak to Mr. Harding in person. Did he not receive my letter?" Harry asks "Who is this, please?" The caller says "I signed the letter only with the name, Roland". Harry says "Just a moment", and transfers the call. David says "Harding speaking". The caller says "Mr. Harding, this is Roland. You received my letter, no?" Harding says "I'd like to know who you really are". Roland says "Full details I cannot give over the telephone, but I give a name, Dr. Maximo. I have been in your country lecturing on Bacteriology. My real purpose was something else, and now I realize I have been making a terrible mistake for years. I can correct it only one way, to tell everything to the United States Counterspies". Harding says "Well, you're only forty five minutes from Washington by train". Dr. Maximo says "Oh no, I do not dare move from this hotel room. My life...." Harding asks "What hotel?" Maximo says "The Gainsborough, Room 819. I beg you to come, Mr. Harding, what I must tell you is of the first importance". Harding says "Well, I'll see about it, Dr. Maximo, good bye" and hangs up the phone. Maximo then calls the hotel front desk and says "Young lady, this is Mr. Jones in Room 819. You have, I believe it is called, a house detective, Mr. Blaine is his name? I believe my life is in danger. Would you please ask him to come to my room at once?" Later, after Harding and Peters listen to a three year old recording of a socialist's speech given in Paris, and compare it to the recording of Dr. Maximo's call from earlier that day, they conclude that it is the same man's voice. Harding says "Well Peters, if this man is ready, as he says, to turn against his masters in Catania, we'd better go see him”.