"The steam-powered tanks produced by Leonardo da Miragliano make for the high water mark of our military engineering genius. Built in 2012 IC, over 500 years ago. Since then we have not advanced our knowledge and techniques — we can hardly maintain Leonardo’s tanks and barely glean his design. Meanwhile, Dwarfs produce innovations with such ease that I feel ashamed to call myself an engineer. What is von Brunel’s sub-hydro velocipator but a flimsy wooden plagiarism of their vastly superior nautilus? Bazalgette’s celebrated cloaca of Kislev a pale imitation of plumbing thought unremarkable in any backwater Dwarf mine. Todmeister's harquebus an unwieldy and slow single-function device compared to the repeating handgun of Mad Makaisson? There are days when I think of packing it in and working in a tannery."
- —Stefan Wenckler, co-creator of the pigeon bomb, in one of his self-reflective moods.[3a]
Karl Herstel and Stefan Wenckler are two Imperial engineers of the Imperial Engineers School of Altdorf. They are best known for inventing the "Pigeon Bomb," a unique and deadly weapon designed to send homing pigeons equipped with explosives towards enemy forces. The idea came after they observed pigeon racing, and they imagined training birds to deliver bombs that would drop once a fuse burned down.