An unusual letter arrived, one day at the Central Post Office of Washington, D. C. Instead of a normal address, there was a note on the envelope, which read: "Go across Sousa Bridge, out Pennsylvania Avenue, turn left at Morton's, and it's the second house from the left." Another letter, sent to Los Angeles, was addressed only "in care of a hotel with a fountain in front." Both letters were delivered to the right person. This small miracle was not due to some extraordinary machine, but to a Nixie. Nixies are the special post office employees who try to find out what the sender had in mind when he addressed his mail. To them go the letters with illegible addresses, incorrect addresses, or no address at all. Nothing much can surprise them. Absent-minded senders write their own name instead of the name of the person to whom they are writing. Others repeat the name of the addressee for the street: "To John Smith, 100 Smith Street, Atlanta,Georgia." Others simply forget to write down the name of the state. In that case, the Nixies have to guess which of the seven Hollywoods, for example, was intended: California, Alabama, Florida,Georgia, Maryland, South Carolina, or Tennessee? There are twelve towns called Paris in theUnited States, sixteen Petersburgs, seventeen Libertys, twenty-two Springfields, twenty-three Malisons, and so on. How do the Nixies do it? They use telephone directories, maps, and postal guides, naturally. But they also rely on their own experience, imagination, and common sense. Sometimes, a simple knowledge of the town is enough to solve an impossible-looking problem, such as the letter addressed: "Cookie -- Salinas, Ca. Ask Smitty." No mystery to the local Nixie, who knew that Cookie was a popular tavern-keeper, and Smitty one of the mailmen. In Washington, D.C., the Nixies don't need books to supply the addresses of Senators, Congressmen, and other officials. Letters to movie stars, well-known athletes, and other famous people do not cause much difficulty either. As for the letters that children send to Santa Claus, they are often forwarded to the local newspapers, who like to publish them before Christmas. But the Nixie in Gary, Indiana, has to be careful; some of the letters may be meant to go to the real town of Santa Claus, Indiana. In small post offices, a Nixie handles several hundred problems per day. In large cities it can be 18,000 or more. But the letters must never be opened. If the Nixies can't guess the address, the letter will go back to its sender. If there is no return address, it will end up in the Dead Letters Centre, where it will be opened for possible information. In hopeless cases, the letters are destroyed after ten days. The Nixies claim 60 percent success. They don't like to give up, and they will try anything to see the problem solved. Once a pair of false teeth was found in a public mailbox. In the same box was a note addressed to the Postmaster, which read: "I have accidentally dropped my teeth in the box. Would you please return them to me?" There was no name and no address. Note and teeth were given to a Nixie, who advertised in the local newspaper in the hope of finding the owner. The teeth were never claimed -- but it was not the fault of the Nixie.The dentist is asked to come to the Central Post Office of Washington, D.C.