Nine-year-old Douglas Cook of Tamaqua wrote a letter to Mayor Frank Walton asking that a "duck crossing" sign by placed on the Elm Street bridge. He is the son of Mr. and Mrs. Robert Cook of East Elm Street. His concern for the safety of ducks crossing in the busy area of Elm Street and Schuylkill Avenue began one day recently when his mother was driving down Elm Street toward the Little Schuylkill River and a little duck waddled onto the road. Mrs. Cook braked hard enough to avoid striking the duck.