The air above the Swift River bridge filled with the shrill, angry scream of three hundred steel-tipped crossbow bolts.
The royal arbalestiers were master marksmen of the Crown, veterans who could drop a running deer at two hundred paces or puncture boiled leather armor through an eye-slit.
Their volley dropped in coordinated, deadly sheets of steel.
Then came the impact.
The heavy iron quarrels didn’t bite into oak or shatter bones. They struck three-quarter-inch Bessemer boiler plate set at an acute forty-five-degree angle along the flanks of The Iron Bastion.
Under the laws of end-post projectiles, an angled armor plate presents an effective thickness far greater than its physical depth.
The effective armor thickness equals the plate thickness divided by the cosine of the impact angle. At forty-five degrees, three-quarters of an inch behaves like more than an inch of solid steel.
The sharp chisel tips of the royal quarrels glanced wildly off the slick, greased steel, losing all striking force in blinding showers of sparks.
