<P> The original song in the film as sung and played by "Sam" was recorded in D - flat major, but it has since been played in several keys, commonly C major, but also B - flat major, as in Frank Sinatra's recording, and others keys including A major and E-flat major . </P> <P> In Casablanca, Wilson sings the Chorus ("You must remember this ..."), but does not sing the Verse ("This day and age we're living in ..."). The omitted lines refer to Albert Einstein . </P>

Who sang the song as time goes by