What is the symbolic meaning of "the salamander devours its tail"?Faber states that when books are found in the homes of firemen, it is going to be...

The salamander is the symbolic name that the fireman give to the fire truck and the symbol for the fireman, himself.  Therefore, if books are found in the home of a fireman, it is self-destructive.  The implements of destruction, in this case, fire, becomes the means by which the salamander actually destroys himself.

The salamander devours his tail is the means that Faber sees as the only way that the society is going to change, the firemen have to change from within.  Just like Montag is a convert, who turns away from his 10 year job as a destroyer of books, he is now a revolutionary who will seek the truth and be part of creating a new society.

The symbol of fire as a means of cleansing and rebirth will have a new meaning as the old society is literally burned off, a new brighter one will rise from the ashes like the phoenix.