In Farenheit 451, What does the Salamander on Mantags arm and the Phoenix Disc on his chest represent?
The salamander logo on Montag's sleeve and the phoenix-disc on his chest symbolically represent the nature of Montag's business as a fireman in Bradbury's dystopian society. As a fireman, Montag is responsible for burning books and the homes of intellectual dissidents. The fireman structure is the government institution in charge of censoring literature, and the firemen use flamethrowers to burn the various illegal texts they discover throughout society. The salamander logo is fitting because it was once believed that they were mythological creatures capable of surviving and living in fire. Similar to the mythological salamander, Montag earns a living by creating flames and setting things on fire. According to Greek mythology, a phoenix was a flaming bird that cyclically regenerated by burning itself every few hundred years and rising from the ashes. The phoenix-disc might symbolically represent Montag's new outlook on life after he quits his job as a fireman and becomes a traveling intellectual. Similar to a phoenix, Montag regenerates himself and seeks to rebuild a literate society after the old society is destroyed by a nuclear bomb.
First of all, the salamander is related to fire since there are ancient, almost mythological, beliefs that salamanders are unaffected by flames and could live in fire. The phoenix also has its place in mythology: it is a bird believed to have cyclically burned itself in flames, only to rise out of the ashes once again. Literally, these symbols are both related to fire and creatures who were believed to survive fire, so it makes sense they'd find their way onto these fictional firemen uniforms. Symbolically, they both, especially the phoenix, represent the idea of rebirth, which is what the resolution of "Fahrenheit 451" is all about - being able to rebuild.
The salamander was known to be a mystical creature due to its ability to live and survive in fire. This relates to Farenheit 451, for Montag is able to live and endure through the burning of books and thus knowledge.
The phoenix was another mystical creature that can be burnt, but would be born again from its ashes. This symbolises rebirth, and it relates to the novel for the wise 'book men' are heading to a beginning of a 'Renaissance', rebirth, of knowledge.