Arlin Adams is one of the city's best known and distinguished lawyers and now after a career that began in 1947 at Schader Harrison, he has decied to retire and devote more of his time to personal interests. To many lawyers in Philadelphia, Adams, a former judge on the U.S. Court of Appeals for the 3rd Circuit, was the soul of judicial and lawyerly discernment. Certainly, many political leaders thought of him that way. He was close to former Gov. William Scranton and former President Nixon and an advisor to former Reagan confidante and Philadelphia publisher Walter Annenberg. Officially, his last day at the firm was Dec. 30. But firm insiders say it is a safe bet he will still be regularly seen in the corridors of Schnader Harrison.