Second Law of Thermodynamics:  According to Rudolf Clausius, creator of thermodynamics as a science, "It is impossible for a self-acting machine, unaided by external agency, to convey heat from a body at one temperature to another body at a higher temperature." William Thomson, Lord Kelvin, a British thermodynamicist, proposed that "it is impossible by a cyclic process to take heat from a reservoir and convert it into work without, in the same operation, transferring heat from a hot to a cold reservoir."  The second law of thermodynamics may also be stated in terms of entropy: in a spontaneous irreversible process, the total entropy of the system and its surroundings always increases; for any process, the total entropy of a system and its surroundings never decreases.

Penda's Fen by David Rudkin: Penda was a king of the Anglo-Saxon kingdom of Mercia in the 7th Century AD.  Penda's Fen was a BBC Pebble Mill production in 1974.  It was a rites-of-passage telecine film about paganism, sexuality and government military conspiracy. David Rudkin is a leading British dramatist, also author of Afore Night Come, Cries from Casement as his Bones are Brought to Dublin, Ashes, The Sons of Light, The Triumph of Death, The Saxon Shore, Symphonie Pathétique, House of Character, Blodwen, and Home from Rachel's Marriage.

p.1
fifteen billion: If this story takes place fifteen billion years after the Big Bang it may be only two billion years in our future.  In Transit the Doctor celebrates the Universe's 13 500 020 012th birthday in 2109, although his veracity in such claims is questionable.  Moreover, most of Dr Who continuity, including Lance Parkin's A History of the Universe follows the premise that after the Big Bang and the period of Universal expansion, the Universe has enough density of mass to halt the expansion and contract in a blue shift or Big Crunch to explode again into the next universe.  Current observations indicate that this is not the case; the Universe will continue to expand and cool.  Over billions and trillions of years hot stars will become extinct, survived by red dwarf stars who will cool and die as black holes and even protons, the building blocks of all matter, decay into radiation whose cooling will be the final whimper of the Universe over a timescale which dwarfs the roughly fifteen billion years since the beginning.

p.2
CVEs: Of course, in the Doctor Who Universe entropy was a much more immediate threat, staved off by opening gateways to funnel matter into our universe from alternate ones.  The Charged Vacuum Emboitements were opened by the Logopolitans before the present day, and when they were temporarily closed by the Master an appreciable part of the Universe succumbed to entropy.  This doesn't scan.  Entropy is not the Big Crunch, and the Monitor is ambiguous as to which concept is the threat.  If the CVEs funnel energy into our Universe, we need a denser Universe to stop entropy, or expansion and cooling.  If the CVEs are for evacuating matter from our Universe, our space is on the point of collapse and the Big Crunch and has too much matter.  Impossibly, continuity says the CVEs funneled matter into the Universe which was already collapsing.  More matter would actually speed the process.

p.11
ten galaxies:

p.13
Ben: Merchant sailor and companion of the 1st and 2nd Doctor.
mercury: Mercury fluid links are a medium of energy storage or transmission in the TARDIS mechanisms, and they periodically run out of or leak the toxic fluid.

p.14
Polly: Debutante, secretary and companion of the Doctor at the same time as Ben.
Daleks, Cybermen, even cutthroat smugglers: In reverse order, the villains which Polly, Ben and the Doctor faced before running out of mercury.  (The Power of the Daleks, The Tenth Planet, The Smugglers)
mercury swamps: "The Power of the Daleks" took place on Vulcan, a rogue planetoid with an abundance of noxious mercury.

p.15
conkers: Traditional English schoolboys' game: hardened horse chestnuts with strings tied around them or knotted through them are swung against each other, and the one whose conker breaks loses.  Continuous strings of conkers wins are a mark of pride.

p.16
recorder: The 2nd Doctor fancied himself a musician, but never improved on this childish and eventually contrived instrument.
Rodean-vintage: All posh.
Miles Davis: Miles Dewey Davis, Jr. (1926-1991), was a jazz trumpeter, composer, and bandleader.  Davis was one of the most innovative musicians of the 1960s and '70s, helping to establish several important jazz styles.

p.17
Sloane Ranger: Unknown, but connected with Ace's suspicions that Polly is a Conservative Party contributions hustler.  On behalf of Anneke Wills, who is clearly not a Tory, I vouch for Polly's character.

p.18
QSO 0046: Quasi-Stellar Object is the first name given to quasars in general; although they look like stars quasars are massive galaxies with huge black holes at their centre.  Accreting material around the black holes radiates extremely large amounts of radiation visible across the Universe.  Quasars can only be seen at the edge of, or near the beginning of the Universe.  Since quasars are so far away light from them can take anything close to the age of the Universe to reach Earth, and there are no quasars in local space.  Since quasars are only seen near the Big Bang, why is there one near the end of time?
wet Wednesday in Margate: Margate is a seaside resort town in Kent on the North Foreland between the Thames estuary and the English Channel.  Wet Wednesdays there are a bit rotten.

p.20
artron energy: obscure mental or temporal force often quoted in vague explanations of regeneration, time travel et cetera.  First used in "The Deadly Assassin".  How Earth scientists could mistake Kirith's artron energy for a quasar is unknown.  Assuming that artron energy is visible and a quasarful can't kill at short range (which a real quasarful can) Kirith is in the whole Universe's future.  If Kirith is visible from Earth it's in the past, and not near the end of the Universe.  Confused?
amoeba: microscopic unicellular organism.
brown duffle coat, porkpie hat, multicoloured umbrella: Mostly wrong.  Although the 7th Doctor did wear a duffle coat in "The Curse of Fenric" he never wore a porkpie hat (like the ones the Blues Brothers wear).  He has always had a straw hat.  He abandoned his multicoloured umbrella, a hangover from the 6th Doctor, in his first serial, "Time and the Rani".  Plus the phrases 'jauntily jammed' and 'his mop of brown hair' are clichéd.

p.21
deltawave augmentor: Electrical brain waves recorded by EEG, or electroencephalogram, are classified according to frequency bands in cycles per second (Hz); delta activity is anything below 4 Hz.  Alpha activity (8 to 14 Hz) is usually produced during periods of relaxation. (Text submitted by Jamal Hannah) the Doctor used a deltawave augmentor on Tegan in "Snakedance" in order to induce her to dream.

p.22
Raphael: Possibly a biblical reference.  Besides being the name of a Renaissance painter Raphael was also the name of an angel sent by God to reward Tobit and his son Tobias, devout Jews in exile in Assyria.  Tobit, or Tobias, is a book in the Old Testament Apochrypha, written (c.200-170 BC) in Hebrew or Aramaic and constructed as a didactic romance. It became popular among Hellenistic Jews and Christians in its Greek translation.

p.25
double heartbeat: So, the Kirithons are half-Gallifreyan.. Time Lords like the Doctor mostly have two hearts, but seriously, other Dr Who races have had them also, such as the Dulcians in "The Dominators". (Text submitted by Paul Andinach) And even Earth-humans in 'The Ark', which is set about the same time as 'Timewyrm: Apocalypse' (cosmically speaking, at least).

p.27
Stones on Salisbury Plain: Stonehenge, the druidic collection of standing stones in a temple in Wiltshire.  Salisbury Plain is much larger than that and is also used for military maneuvres.  Stonehenge is on the A303 (or whatever it's called now) west of Amesbury, ten miles north of Salisbury.

p.28
Kremlin: Central citadel of Moscow, not to mention many other old Russian cities.  From the Russian kreml, meaning "fortress".  Although the Kremlin harbours several palaces or buildings of note, Ace probably means St. Basil's Cathedral, the onion-domed church which is just outside.
Mont St Michel: French tourist attraction, but not in Normandy.  Mont St. Michel is in Ille-et-Vilaine on the Golfe se St.-Malo south of the Channel Islands.  It's a citadel on a tidal plain, linked to the mainland by a causeway which is underwater at high tide.  The English equivalent St. Michael's Mount is at Marazion on Mount's Bay in Cornwall.
King Charles: Possibly the current Charles, Prince of Wales, who has architectural leanings.  Also possibly Charles II of England, who helped to direct the rebuilding of London in 1666 along with Christopher Wren, who did St. Paul's Cathedral.

p.29
yesterday sunbathing, tomorrow snow; just like England: The United Kingdom has a highly variable temperate marine west-coast type of climate.

p.30
porphyry: Porphyry is an igneous rock of any composition composed of phenocrysts surrounded by a groundmass of fine-grained crystals.

p.32
murdered in my bed: Ace's concern is common to Minnie Bannister, an aged character in The Goon Show, a BBC radio program of the 1950s.  'We'll all be murdered in our beds' is her catch phrase.

p.32
Manisha: Childhood friend of Ace's, and member of a visible minority.  First mentioned in a McCoy-era novelisation, the firebombing of Manisha's house by skinheads and her subsequent death from smoke inhalation is one of Ace's major formative experiences.  However, in this version Manisha appears to have survived.

p.34
Portobello Road: Trendy street in Notting Hill, West London.
cholestrerol gunk at Mrs Smith's boarding house in East London: In "Remembrance of the Daleks" Ace and the Doctor stayed here with soldiers of the Intrusion Countermeasures Group, including Mrs Smith's neo-nazi son Sgt. Mike Smith.  Mrs Smith had a 'no coloureds' sign outside her door, and probably served bad sausages, which in itself is no surprise.

p.37
Alzarius: home planet of the child prodigy Adric, in E-Space.  The Alzarian ecosystem incorporated Adric's people and sped up their metabolisms, which sped up their healing process as well as their evolution.

p.41
Captain Hook: Villain of James M. Barrie's Peter Pan (1904), in which a swashbuckling fairy, Peter Pan, whisks off several children to fight the evil Hook in Never-Never Land.

p.48
ticket to Marx: Karl Marx was one of the more famous patrons of the British Museum.  He did research for the Communist Manifesto in the reading room there.
Pope Clement - Vatican Library: The Museo Pio-Clementino, founded (late 18th century) by Clement XIV and Pius VI, is devoted entirely to Greek, Hellenistic, and Roman art.  Alternatively, the Vatican Library was designed by Domenico Fontana and executed between 1585 and 1590 during the papacy of Sixtus V.  Fontana was deprived of his post by Pope Clement VIII in 1592.
Alexandria library - Aristophanes: Aristophanes (445-385 BC) was the greatest comic dramatist of ancient times and is the only representative of the Athenian style known as Old Attic Comedy still in print.  Aristophanes is believed to have written more than 40 plays, although only 11 survive.  The Library of Alexandria was founded by Ptolemy I, formerly one of Alexander the Great's generals, in the 3d century BC.  Scholars there copied, revised, collated and edited works of the classical Greek writers.  The library flourished for several centuries and held about 500,000 papyrus scrolls.  The library was scattered in the 4th Century.

p.49
early hominids: Homo habilis probably first appeared between 1 1/2 and 2 million years ago, in Africa.

p.50
Hiroshima, descendant of the bone: Typical simile as used in "2001: A Space Odyssey".  On August 6, 1945 a 12-kiloton uranium bomb was exploded above Hiroshima.
Them that ask no questions don't get told no lies: Ancient proverb of unknown derivation.  This version contains a double-negative, so presumably even if you do ask questions, feel safe that no lies will be told to you.

p.51
bread and butter pudding: Scald one quart of milk and soak five or six cups soft bread crumbs and one cup sugar in it.  Rub the mixture through a fine seive.  Beat together four eggs and six yolks and combine them thoroughly with the bread crumb mixture.  Fold in four egg whites, beaten until stiff.  Butter a tall 2-quart cylindrical mold, sprinkle it with fine dry bread crumbs, and fill it with the mixture.  Set the mold in a deep pan of hot water and bake the pudding in a moderate oven (350°F) for about 40 or 45 minutes, or until it is firm.  Let it stand for about 15 minutes before unmolding it onto a serving dish.  Serve hot or warm with vanilla or sabayon sauce, or any fruit sauce.  Not much butter, but you can get too much these days.  Thank you, the Gourmet Cookbook Volume 2 by Gourmet, the Magazine of Good Living.

p.54
Omega: 24th and last letter of the greek alphabet.  It has great philosophical significance and is often used to represent the end of things.  W or w.

p.55
regenerated: The 2nd Doctor was introduced soon before this sequence; he regenerated from the 1st Doctor's form after "The Tenth Planet", and this sequence follows "The Power of the Daleks", the next story.

p.56
Professor Travers: 20th-century anthropologist and acquaintance of the 2nd Doctor.  In "The Abominable Snowmen" Travers was searching for Yeti in Tibet in the 1930s, and helped the Doctor defeat robotic Yetis animated by an alien intelligence.  In "Web of Fear" he was there to help defeat the Yeti again, this time in the London Underground in the late 1960s.

p.58
primeval slime: The first forms of life, apparently universally, were constituted in tidal pools, near hydrothermal vents on sea floors or in wet layers of clay from films of tar, hydrocarbons and oils and amino acids.  So the phrase primeval slime pretty much applies here in any context you care to nail it to.  But the Kirithons didn't wade out of it fully-formed as a species; how about 'I wonder how your nucleic acids ever dragged themselves together in the primeval slime.'
escape velocity: The minimum speed that a projectile or spacecraft must attain in order to escape the gravitational field of a celestial body such as a planet.  Earth's escape velocity is 6.9 miles per second, or 11.2 km per second.  Kirith's is a little under 6.5 m/s or 10.5 km/s.  Not to be pedantic, but the Doctor has said Kirith has Earth-normal gravity.  The value of the escape velocity depends on the mass of the planet and varies with the distance from the planet.  On p.62 Kirith is revealed to have a 16 1/4 hour day.  And it also has two moons with relatively stable orbits, which is unlikely for such a small planet.  The Kirithon tides must be huge, but fortunately there aren't any other planets in the system to destabilise the orbits any faster.  So orbital dynamics have been thrown to the wind.

p.61
concrete monstrosities in Perivale: Perivale is a London suburb of housing projects, playing fields and common land.  Take for example the Medway Parade flats where the scenes in Midge's flat for "Survival" were filmed, or Horsenden Hill, the reservoir, golf course and scrublands used for the motorcycle duel in the same story.

p.62
16 1/4 hours: Sorted.

p.67
Sellafield blues: Sellafield is a nuclear power site on the Irish Sea which has had a number of misadventures with radioactive materials being released into the environment.

p.71
Italian friend - telescope: The Doctor is alluding to Galileo Galilei, the Italian scientist who first used the telescope for astronomical observations.  If the telescope used was one of Galileo's it wouldn't matter much if Miríl did have it the right way round; Galileo's optics were very poor.  Besides, he didn't even invent the telescope, it was Hans Lippershey in Holland in 1608, one year earlier.

p.73
tor: A high rock; a pile of rocks, gen.on the top of a hill; a rocky peak; a hill.  In proper names of eminences or rocks in Cornwall, Devon, Peak of Derbyshire; also sporadically in some other counties, e.g. Glastonbury Tor, in Somerset.

p.74
carbon-14 test: Carbon-14 is an isotope of carbon produced in the upper levels of the atmosphere from nitrogen isotopes and cosmic rays.  Incorporated into carbon dioxide, it is taken up by green plants in the course of photosynthesis.  When the organisms die, the carbon-14 decreases with time at a well-established rate.  Willard Libby developed the method of dating organic material by measuring radioactivity from carbon-14.  The carbon-14 test can date samples as old as 35,000 years, although 10,000 years has been the more practical limit.  Dead on, Nigel.

p.76
Gothic splendour: Gothic architecture is not easily defined.  Although rib vaulting and the pointed arch are its most characteristic features, both were widely used in Romanesque churches.  Only when diagonal ribs are used in direct conjunction with pointed transverse arches in the vaulting of an interior can a structure be identified as Gothic.  This type of rib vaulting was the decisive factor in the evolution of the French cathedrals such as Chartres and Notre Dame de Paris, where vaulted interiors of unprecedented heights were constructed and Romanesque walls were discarded in favour translucent walls of stained glass.
Auschwitz and Treblinka: Oswiecim, a town in southern Poland, was the site of a Nazi concentration camp during World War II.  Large numbers of people, variously estimated at from 1 to 3 million, were killed in the Auschwitz camp.  Treblinka was a concentration camp 80 km from Warsaw, Poland.  Treblinka was turned into a death camp early in 1942.  By July 11, 1945, when the Soviet army entered Warsaw, 800,000 Jewish men, women, and children had been put to death at Treblinka.

p.78
cans of nitro: Ace has apparently run out of nitro nine-A, the marble-sized explosives capsules from the previous novel.
Hammer Horror: Franchise of filmed-in-England horror movies with such actors as Christopher Lee and Peter Cushing; known for Sherlock Holmes, Dracula, and Frankenstein remakes.

p.83
burette: A graduated glass tube for measuring small quantities of liquid.

p.94
zavàt: Feeding people with processed human remains is not a new idea; soylent green, from the film of the same name, is remembered for the Charlton-Heston-uttered catch-phrase "Oh my God, soylent green is people!"
Jamie: 18th-Century Highland Scottish piper and companion of the 2nd Doctor.

p.95
The pen is mightier than the sword: Edward Bulwer Lytton.  "Beneath the rule of men entirely great, The pen is mightier than the sword. Richelieu. Act ii. Sc. 2.

p.98
apotheosis: The action of ranking, or fact of being ranked, among the gods; transformation into a god, deification; divine status.

p.101
codswallop: Worthless, ridiculous, nonsensical ideas, discourse or writing.

p.102
multi-ident trimonic lock: (Text submitted by Jamal Hannah) reference possibly to the TARDIS mechanism in 'The Deadly Assasin' and 'The Invasion of Time' and definitely to Greel's cabinet in 'The Talons of Weng-Chiang'.
logic key:

p.105
Edwardian: relating to the period of time of the reign of King Edward VII, between 1902 and 1910; an age of playboys, sportsmen, traveling and the arts for the middle class set, not just the aristocracy.

p.107
21st-Century Australia: First setting of the 2nd-Doctor serial "The Enemy of the World" which follows this sequence.
Will's house: William Shakespeare's house in Stratford.  Shakespeare probably abandoned this house, his wife and their two children before authoring his plays in London around 1600.
Alpha Centauri: Multiple-star system and the closest solar system to our own, roughly 4 light-years away in the southern constellation of Centaurus, in which it is the brightest star.  The Alpha Centauran race in Doctor Who are androgynous hexapods with something extra to stand upright on, and heads consisting of a single huge eyeball with pulsing veins and a blinking mechanism (although their likeness to another organ entirely has been remarked upon).

p.112
Gordon Bennett: Mild British expletive, as used by Ace on several previous occasions.

p.120
Chernobyls: More of a metaphor than a unit of measurement, the term refers to the Chernobyl nuclear accident in the Ukraine in 1986, when a mismanaged nuclear reactor melted down and irradiated the environment and population.

p.125
Rottweiler: A breed of dog similar to the Doberman pinscher in outline but much more massive and with comparatively small ears set high, carried flat, and hung over to the side of the head.  The short, smooth, glossy coat is black with clear tan to rust markings.

p.127
Louis Armstrong: Louis "Satchmo" Armstrong (1900-1971) was a brilliant American jazz cornet and trumpet soloist.
Music hath charms to soothe the savage beast: William Congreve (1697) Mourning BrideI.i,"musick has Charms to soothe a savage Breast"
Venusian lullaby: Ridiculous alien melody intoned by the 3rd Doctor to the tune of God Rest Ye Merry Gentlemento mesmerise Aggedor, the Royal Beast of Peladon, in the two Peladon serials: "The Curse of Peladon" and "The Monster of Peladon".
William Congreve: The English dramatist William Congreve (1670-1729) was one of the most polished comic stylists of Restoration Drama.

p.130
I will not revert to being a savage again!: In "Survival" the Doctor was partially turned into one of the Cheetah-People.  And this is a damn good turn of phrase, too.

p.137
blew up the art room: At the climax of Episode 1 of "Battlefield" Ace subtly related the fine anecdote of how she had exploded the art room at her school.

p.138
Joe Public: Everyman.

p.142
Miss Sydenham in Computer Studies playing Space Invaders: In "The Curse of Fenric" Ace mentioned her CS acher was Miss Birkett.  However, in Ian Briggs' original script and possibly the serial's novelisation tacher was named Miss Sydenham.  Space Invaders was the most popular Nolan Bushnell video game in which a moveable cursor fires at an even-oncoming line of shapes representing spaceships.  Space Invaders supplanted Pac-Man, Tank, Gotcha, Space Race and the fabulous Pong in the late 1970s. (Text submitted by Paul Andinach) Yes, it's Miss Sydenham in the novelisation as well.

p.159
Godzilla: Monster horror movie star in Japan and the United States.  Awakened by nuclear weapons tests at sea, the hundred-metre dinosaur Godzilla swims to shore and stomps on the nearest city, either Los Angeles or Tokyo and sets fire to it with his nuclear fire-breath.

p.161
Brigadier: Brigadier Alistair Gordon Lethbridge-Stewart, a 20th-Century military officer and companion of all 7 Doctors.

p.164
Lilith: Adam's first wife from the Babylonian creation myth.
Loch Ness Monster: Mythical sea-monster inhabiting the Scottish Loch Ness.  In "Terror of the Zygons" Nessie was revealed to be a Skarasen, a cyborg amphibian who produced milk for the villainous shape-shifting Zygons' consumption and attacked oil rigs on their orders.

p.165
football pitch: 110 yd (100 m) long and 75 yd (69 m) wide.

p.166
Greenford disco: Greenford Road, the A4127, is an arterial road which runs from Southall through west Perivale, turns into Sudbury Court Drive and ends at a roundabout on Watford Road in North Wembley, just south of Harrow School.  There's probably a club on it, as it was also mentioned in "The Curse of Fenric".

p.182
tinderbox: A box in which to keep tinder, as well as flint and steel to strike a spark and brimstone matches to keep it.  Unlikely to actually explode.

p.188
old house: As a child Ace was so scared of Gabriel Chase, the derelict mansion she later visited in an earlier time period ("Ghost Light") that she set fire to it and burned it to the ground.

p.189
Mike: Sgt. Mike Smith, the soldier of which Ace was enamored in "Remembrance of the Daleks" before she discovered that he was both a neo-nazi and a Dalek agent.
Sorin: Soviet officer of which Ace was enamored in "The Curse of Fenric" before he was taken over by an evil intelligence from the beginning of time.
Karra: Anthropomorthic cat in "Survival" who tried to convert Ace to one of the Cheetah-People.

p.201
Pull the other one: Means 'I believe you're bluffing, you're joking so lay out your cards.'