The big weapon was intended for computer-directed air defense. Under manual control, its sights were only a little more sophisticated than those of shoulder-fired powerguns: a hologrammatic sight picture with a bead in the center to mark the point of impact.
Nothing more was required.
Several of the guards turned when the grenades went off, instinctively looking for escape and instead seeing behind them the calliope's lowered muzzles. One of the orderlies got off a burst with his submachine-gun.
The bullets missed by a hundred meters in the two blocks they were meant to travel. Concrete, steel, and flesh—most particularly flesh—vaporized as the calliope chewed across the stair head in a three-second burst.
Desoix switched to intercom with the hand he didn't need for the moment on the elevation control and said, "Lachere, advance toward the stair head at a—"
Faces appeared around the seawall just north of where the bollards had been before the gun burned them away. The high-intensity 3cm ammunition had shattered concrete at the start of the burst before Desoix traversed away. His right hand rolled forward on the twist-grip, reversing the direction in which the barrel array rotated on its gimbals.
More of the wall disintegrated in cyan light and the white glare of lime burned free of the concrete by enormously concentrated energy. Most of the rioters had time to duck back behind the wall before the second burst raked it.
The wall didn't save them. Multiple impacts tore it apart and then flash-heated the water in their own bodies into steam explosions.
Beneath Desoix, the skirts of the calliope's plenum chamber dragged the pavement. Air had enough mass to recoil when it was heated to a plasma and expelled from the eight tubes as the gun fired. Lachere drove forward, correcting inexpertly against the calliope's pitch and yaw.
Gunfire was a blue-green shield against the roar from the plaza, but in the moments between bursts the mob's voice asserted itself over the numbness of ringing breech blocks and slamming air.The stair head was now within a hundred meters as the gun drove onward. There was a haze over the target area—steam and dust, burnt lime and burning bodies.
Desoix's face shield protected him from the sun-hot flash of his guns. Events, thundering forward as implacably as an avalanche, shielded him from awareness that would have been as devastating to him as being blinded.