The mystery of the missingcouple was solved by the U. S.mail today.Police Chief Clarence Walker received a postcard from Mrs. Jim Lingo, asking that some of the couple’s property being held at the police department be sent to the pair. The card was postmarked Alleene, Ark.Mr. and Mrs. Lingo had been the objects of a widespread search since they had disappear-, ed from their trailer home at the city dump, where Lingo acted as unofficial caretaker. Their truck, two trailers and all their belongings, except for some articles still smouldering in a pile of burning rubble, had vanished with them overnight.Investigating officers had feared possible foul play; but eventswhich had all the earmarks of a first-class mystery faded into the commonplace with the card’s arrival.Chief Walker opined today that he still intended to write the Lingos for an explanation of their sudden decision to pull up stakes.