1. For more than a hundred years, there was only one subway system on Mars. It was one of those things that the colonists complained about, along with the red dust that got on everything and the air company ice-cream machines, which were broken more often than not. The subway was at Lycus Sulci, in the administrative centre, and it only had five stops. In its third year of operation there was a dust avalanche at Crater Wall Station and, when everything had been cleaned out, the tracks were slightly buckled. Ever since that time, commuters to the colonial headquarters could hear a faint tune behind the electric hum of the railway as the trains reached the end of the line. There was a rumour that it was the same tune that had been heard in the Great Pyramid at Giza, five days before its destruction.
2. In time, the air company removed the ice-cream machines and moved its workers from pay in cash to pay in company store tokens, citing increased costs for solar panel components. The colonial court upheld the legality of this decision. One morning, fifty air-company workers were trapped on a malfunctioning train carriage, shuttling back and forth between imaginary stops at the end of the line. When they were finally rescued, they marched on the company’s headquarters, singing the railway song to some words of their own invention. There were riots, and the garrison at Gordii Dorsum was called in.
3. Later on, after the Battle of Abus Vallis and the Breathless Days, after the Easter Ceasefire and the Great Turning-out, the song became the anthem of the Republic of Olympus Mons. It was said to have been an ancient African song, sung by slaves rebelling against unjust kings. They had always intended to send an ambassador back to the Court at Kigali to investigate further, but somehow they were always too busy with Mars matters.
4. Eventually, something went wrong with the colony’s genetic improvement program. An age of perpetual embarrassment began. It is very difficult to decipher any of the writings from that time, because they could perform prodigious acts of euphemism; their medical notes were like epic poems. They are known to have invented a new kind of excretion, referred to on occasion as ‘Number three’. They became known as a people who could fill a conversation entirely with the minutiae of dust and who lived out their lives in private rooms.
5. On the other side of Mars, where there were five more baby republics and an emperor with maybe fifty subjects, they sung a mocking version of the song and it was about people who cannot say what they mean. They were still singing the song after the end of the Republic of Olympus Mons, which was overrun by genetically-modified attack pandas from the Air Company who sneaked in whilst all the Republic’s Sentries happened to all be enjoying a leisurely Number Three at the same time.
6. The baby republics had ice-cream machines, and they were all planning to build subway systems, and they had engineered a kind of ivy that grew in the thin air of the plains and produced a reasonable facsimile of vanilla pods. It was their efforts that eventually made Southern Mars the dessert capital of the Solar System. Visitors came from all over. The shuttle company calculated fuel requirements under the assumption that they would leave a kilogram or two heavier than when they had arrived. In those days, the song was sung in custard parlours; it was said to be a lament for the great library at Alexandria.
7. Inspired by the song, the baby republics ploughed the custard-parlour profits into a great university, which survived and grew beyond the days when custard-parlours were considered hopelessly old-fashioned. In time, seven of the drowned Oxford colleges relocated there, and two from Cambridge. In those days the streets were dug into canals, and the university, which was in itself also a city, resembled a Venice that had never been dusted.
8. The university had a hundred years in which it was obsessed with time. During those years, a child grew up who had been sung the song in her cradle, and whenever she was uncomfortable thereafter she would hum it to herself. Eventually, she inherited an office in the Faculty of Time and discovered three of the seven secrets of time travel, which she refused to share with her collaborators. Instead, she determined to travel back to the destruction of the library at Alexandria. Lacking the Fourth Secret, however, she could travel only back as far as the destruction of the pyramids; and without the fifth secret, she was not able to travel to public places; and without the sixth secret she could not quite control her final location. Thus it was that she found herself in a secret chamber of the Great Pyramid, and her equipment to get home in another secret chamber, and no way of knowing quite when she was. Undeterred, she chipped away at the separating wall, singing the song to herself the while. After five days, her return equipment self-destructed, destroying the pyramid. As it happened, one of the local warring parties had been setting explosives in the pyramid the whole while in any case, so they were only too happy to take responsibility. But the soldiers never forgot that the pyramid had serenaded them with its death song, before it finally crumbled into dust.