Roosevelt Thomas Williams, 92, a blues pianist known as the Grey Ghost. Williams got the nickname early in his career, he once explained, because of his knack for showing up immediately before a performance and disappearing immediately afterward. Welcoming parties waited futilely at train stations and bus stations, never realizing he was riding the rails hobo-style. Williams said he wore overalls over his suit and tie and benefited by knowing railroad workers throughout Texas. Born in Bastrop, Texas, he was adept at several musical styles--blues, jazz, boogie-woogie and barrelhouse piano. Williams semiretired in 1965, but made a comeback in 1987 and released his first album in 1993. He wrote many of his own songs, including “Hitler Blues,” “Why We Can’t Agree,” “Ida B” and “Crack Shack Boogie.” On Wednesday in Austin, Texas.