NEITHER RAIN, NOR SLEET, NOR MORE THAN 40 YEARS ...

It was a sleuthing job that would have done Sherlock Holmes proud. Except that the United States Postal Service was not looking for criminals: It was searching for 92 World War II servicemen. The 235 letters that they had written aboard a troop ship in May 1944 never were mailed and turned up 42 years later in a North Carolina attic. Postal officials decided to return them to the writers.

Before the 2 year search was over, the Postal Service had enlisted the help of the Veterans Administration, the news media, friends, relatives, and strangers. When one letter was returned, the ex-serviceman dutifully delivered it to the addressee - his mother, then in her 90s.

Today the Postal Service will stamp success on this mission. In a Washington ceremony, Postmaster General Anthony M. Frank is to return the last two letters to the brother of the writer, Sgt. Clarence F. Smith, who was killed two months after putting pen to paper.

Finding Norman T. Smith took the combined efforts of a dentist in Washington state, a librarian in Maryland, and the 781st Bomber Squadron Association. If success were only as certain in delivering today's mail....