He broke off as a frantic call came in from the Pittsburgh station for the Commissioner; a call which Samms both heard and saw. "The city is being attacked!" came the urgent message. "We need all the reenforcements you can send us!" and a picture of the beleaguered city appeared in ghastly detail upon the screens of the observers; a view being recorded from the air. It required only seconds for the commissioner to order every available man and engine of war to the seat of conflict; then, having done everything they could do, Kinnison and Samms stared in helpless, fascinated horror into their plates, watching the scenes of carnage and destruction depicted there. The Nevian vessel--the sister-ship, the craft which Costigan had seen in mid-space as it hurtled Earthward in response to Nerado's summons--hung poised in full visibility high above the metropolis. Scornful of the pitiful weapons wielded by man, she hung there, her sinister beauty of line sharply defined against the cloudless sky. From her shining hull there reached down a tenuous but rigid rod of crimson energy; a rod which slowly swept hither and thither as the Nevians searched out the richest deposits of the precious metal for which they had come so far. Iron, once solid, now a viscous red liquid, was sluggishly flowing in an ever-thickening stream up that intangible crimson duct and into the capacious storage tanks of the Nevian raider; and wherever that flaming beam went there went also ruin, destruction and death. Office buildings, skyscrapers towering majestically in their architectural symmetry and beauty, collapsed into heaps of debris as their steel skeletons were abstracted. Deep into the ground the beam bored; flood, fire, and explosion following in its wake as the mazes of underground piping disappeared. And the humanity of the buildings died: instantaneously and painlessly, never knowing what struck them, as the life-bearing iron of their bodies went to swell the Nevian stream. Pittsburgh's defenses had been feeble indeed. A few antiquated railway rifles had hurled their shells upward in futile defiance, and had been quietly absorbed. The district planes of Triplanetary, newly armed with iron-driven ultra-beams, had assembled hurriedly and had attacked the invader in formation, with but little more success. Under the impact of their beams, the stranger's screens had flared white, then poised ship and flying squadron had alike been lost to view in a murkily opaque shroud of crimson flame. The cloud had soon dissolved, and from the place where the planes had been there floated or crashed down a litter of non-ferrous wreckage. And now the cone of space-ships from the Buffalo base of Triplanetary was approaching Pittsburgh hurling itself toward the Nevian plunderer and toward known, gruesome, and hopeless defeat. "Stop them, Rod!" Samms cried. "It's sheer slaughter! They haven't got a thing--they aren't even equipped yet with the iron drive!"