Fitting a sound guidance bridle to a fifty-mile underground World-Wyrm was, as Giles Croft explained to his senior engineers, fundamentally an exercise in civil sound mechanics.
Across the broad terrace of Quarry One, Master Duncan Stone-Splitter and sixty dwarven rigger-smiths had spent two days weaving a master harness from four-inch braided Manila hemp and flexible spring-steel bands.
Suspended along the cheek straps were twelve tuned copper deep ring bells, each cast to ring at a precise sound pitch when struck by an air-powered hammer.
“Terravorax navigates underground rock via sound echo-location,” Giles explained. He stood on the staging overhead frame as the harness was hoisted into place by four mobile cranes.
“A low C-sharp indicates a forty-five-degree starboard bank.
A high G-natural signals a thirty-degree dive.
And when the beast follows the bearing true, we reward it with fifty bushels of soft white spar-stone limestone aggregate infused with sugarcane syrup.”
During the harness fitting at Quarry One, Aldous Swift-Current had spent eight hours calibrating the twelve tuned copper bells suspended along the bridle cheek straps.
