It's no coincidence that the speaker in "Rook" calls on these birds when seeking knowledge of the present, the future, and the hereafter. All of the crow family - rooks, crows, ravens, magpies, and jays - are associated with hidden knowledge and foretelling the future. The well-known counting rhyme, applied in different variants to both magpies and crows, is an example of this:
One for sorrow, two for joy
Three for a girl, four for a boy
Five for silver, six for gold
And seven for a secret that can't be told.
As this rhyme makes clear, crows and their kin are augurs, keepers of secrets and mysteries. The Roman author Suetonious recounts the tale of a prophetic crow, a pet of the Emperor Domitian, who could talk, but would only say "All will be well." Because of their habit of saying "cras! cras!" ("Tomorrow! Tomorrow!"), crows also became a symbol of hope - as well as procrastination.
The crow family is also associated with death, both because of their black feathers and their habit of feeding on carrion. Ravens and crows alike were considered to be incarnations of the Valkyries, Norse warrior goddesses that roamed the battlefield searching for the souls of the dead, and the raven was a symbol for the Morrigan, the Irish death-goddess.
A rook.
There are no specific legends associated with rooks, but according to author Neil Gaiman, they do have one mystery. A group of rooks is known as a parliament, due to their habit of forming large assemblies during which one bird will seem to "speak" or orate at length. Afterwards, the bird is either left alone or torn to pieces. Gaiman claims that the lone bird is telling a story; the other birds' reaction is their form of criticism.
With all of this in mind, it's not surprising that Andy Partridge should have chosen to depict the rook and the crow as possessors of hidden knowledge. Other musicians have done likewise, both in modern times and in the past, as in Schubert's song "Die Krähe" ("The Crow"), a song very similar to "Rook" both thematically and in its sad, bleak mood, or as in Robyn Hitchcock's song "The Black Crow Knows":
If you want to know what the future holds
The black crow knows.
It's significant, though, that both in Schubert's song and in "Rook," the mysterious birds never answer the questions put to them; they choose to keep their secrets.
