A Journal of Impossible Things (Human Nature)

A Journal of Impossible Things was a journal kept by John Smith of his strange dreams. In reality, the book was comprised of events he'd experienced as the Doctor. All but Martha Jones, the only person who knew his actual identity, believed these to be products of John Smith's imagination.

History
After turning himself human to hide from the Family of Blood, John Smith began to experience dreams of his adventures as the Doctor. He scribbled these down, adding detailed sketches throughout.

Smith gave the book to Joan Redfern, (TV: Human Nature) who apparently annotated it with a detailed chronicle of her love story with a strange visitor from beyond the stars. In the 21st century, this annotated version of the book fell in possession of her great-granddaughter, Verity Newman, who used it as the basis for own book of the same name. (TV: The End of Time)

Illustrations
Among the many illustrations Smith made in his journal were:
 * The TARDIS
 * The TARDIS Console
 * Steaming TARDIS Console
 * Sonic screwdrivers
 * TARDIS Crystal
 * New Gallifreyan words
 * Torchwood Institute logo
 * Empty People
 * Gas mask
 * Dalek top
 * Dalek Saucer
 * Dalek
 * Cybermen
 * Cyberman Faceplate
 * Vortex Reapers
 * The Doctor's first nine incarnations (aside from the War Doctor)
 * Rose Tyler
 * Family of Blood
 * Fob watch
 * The Moxx of Balhoon
 * Autons
 * Raxacoricofallapatorian
 * Big Ben
 * Raxacoricofallapatorian Inter-Stellar Transporter
 * Mighty Jagrafess of the Holy Hadrojassic Maxarodenfoe
 * Satellite Five (The Game Station)
 * Cat Nurses
 * Lupine Wavelength Haemovariform
 * K9
 * Clockwork Droid
 * Martha Jones
 * Joan Redfern
 * Dalek Emperor
 * Anne Droid
 * Captain Jack Harkness
 * Pilot fish
 * Fadros Pallujikaa
 * London Eye
 * London Eye Capsule
 * Rose's face on television set
 * Ood
 * The Beast
 * Toby Zed
 * Tenth Doctor
 * Empire State Building
 * William Shakespeare
 * Shayde (PROSE: "Extract from 'A Journal of Impossible Things'")
 * War Doctor, only partial as if burnt from the page (PROSE: "Extract from 'A Journal of Impossible Things'")
 * Special Weapons Dalek (PROSE: "Extract from 'A Journal of Impossible Things'")

Behind the scenes

 * An actual, intricately-illustrated prop book was created for the filming by artist Kellyanne Walker. Later, Character Options, which held some of the rights to release toys and merchandise based upon the series, issued a faux leather-bound reproduction of the book. The CO journal is not as big as the one in the episode.
 * The images of the Doctor appearing in the journal were taken from a collage of past incarnations used as the illustration for the Wikipedia article on the Doctor, though they were inverted.
 * In the original novel Human Nature, John Smith did not write a journal, but a children's story, The Old Man and the Police Box, which similarly echoed events in the Doctor's life; however, that story contained more radical implications that the Doctor was originally a Victorian human who had single-handedly invented the TARDIS, discovered Gallifrey and founded Time Lord civilisation, none of which is suggested in A Journal of Impossible Things.