I'm not sure whether this information has been posted before, but it may interest anyone who (like me) has wondered about the connection between F451 and various short stories such as "Bright Phoenix" and "Usher II".

The following information comes courtesy of Jon Eller, co-author of Ray Bradbury: A Life of Fiction (still waiting for my copy, Amazon!):

============
The five analogs to The Fireman (and eventually Fahrenheit) were all written between 1948 and 1950. They are Bright Phoenix, The Bonfire, Pillar of Fire, The Exiles and Carnival of Madness (Usher II). The precursor to Usher II is The Castle, still unpublished. It previews Usher II closely, but it is a completely different text. Needless to say, the pre-McCarthy HUAC period provided the principal cultural inspiration. But the immediate F451 catalyst is, oddly enough, The Pedestrian (written 1950; published 1951). In his mind's eye, Bradbury's pedestrian suddenly became Montag, turning a corner and encountering Clarisse; he has never met her, but she says, "I know who you are."

The true trying out of Fahrenheit survives in an unpublished novel from the late 1940s, titled Where Ignorant Armies Clash by Night. In our book, Bill Touponce examines how the Assassin of that manuscript became the Fireman, as Bradbury searched for a more effective way to portray the crisis of values in our post modern culture. The manuscript is fragmentary, and the only portion that was ever published is "The Smile" (1952). This is why the original work remains undetected today, unless one examines the full manuscript record of this period.
============

This last paragraph came as news to me, and convinces me that Bradbury is a relentless re-writer and re-purposer!

- Phil