This little detail — which was entirely and solely my doing (it's my book, after all) — escaped all the readers who looked over the book in various official and unofficial capacities. It's far too late to fix the hardback now. So when you buy your copies of Escapement (as you all are planning to do, right?), please take a blue pencil, and wherever you see the word "Java", gently cross it out and write in "Sumatra".
Ah, the bliss of geographical ignorance. I am so damned embarrassed.