So. The Clacks. Ah, the Clacks! For the purposes of his story Pratchett needs to create a sense of almost otherworldiness around the clacks, a sense that it’s more than just a machine, and he does it brilliantly. From The Grand Trunk*, the name of the main line of semaphore towers which runs from the highest point in Ankh-Morpork, The Tump (the huge semaphore tower atop it therefore being known as The Tump Tower, ho ho) to Genua via Uberwald and Borogravia, to the technical jargon (jacquard, drum, signature card, code), to the slang used by the (mostly young, mostly geeky operators): Sending Home, Living in the Overhead, The Hour of the Dead; it’s a complete and entirely believable subculture.
And now my supper is ready, so More Tomorrow.
* Also the name of the owning company, which therefore controlled communication between Ankh-Morpork and its mercantile partners, rather as the East India Company virtually owned all trade between Britain and the Indian subcontinent in the 19th century, and, incidentally, the name of one of Asia’s oldest and most important roads, between Chittagong in Bangladesh and Kabul in Afghanistan. Interesting, huh? He were no fool, that old Mr Pratchett….