The other fort had its screen up, though its power, designed to withstand the attack of a fleet of enormous intergalactic, matter-driven, fighting ships lasted but an instant under the driving power of half a million million suns, concentrated in one enormous ray of energy. The sheer energy of the ray itself, molecular ray though it was, heated the material it struck to blinding incandescence even as it hurled it at a velocity close to that of light into outer space. With little sparkling flashes battleships of the void after giant cruisers flashed into lux, and vanished under the ray. A tremendous combined ray of magnetism and cosmic ray energy replaced the molecular, and the ships exploded into a dust as fine as the primeval gas from which came all matter. Sweeping energy, so enormous that the defenses of the ships did not even operate against it, shattered ship after ship, till the few that remained turned, and, faster than the pursuing energies could race through space, faster than light, headed for their base. "That was fair fight; energy against energy," said Arcot delightedly, for his new toy, which made playthings of suns and fed on the cosmic energy of a universe, was behaving nicely, "and as I said, Stel Felso Theu, at the beginning of this war, the greater Power wins, always. And in our island here, I have five hundred thousand million separate power plants, each generating at the rate of decillions of ergs a second, backing this ship. "Your world will be safe now, and we will head for our last embattled ally, Sirius." The titanic ship turned, and disappeared from the view of the madly rejoicing billions of Talso below, as it sped, far faster than light, across a universe to relieve another sorely tried civilization. Knowing their cause was lost, hopeless in the knowledge that nothing known to them could battle that enormous force concentrated in one ship, the _Thought_, the Thessians had but one aim now, to do all the damage in their power before leaving. Already their tremendous, unarmed and unarmored transports were departing with their hundreds of thousands from that base system for the far-off Island of Space from which they had come. Their battlefleets were engaged in destroying all the cities of the allies, and those other helpless races of our system that they could. Those other inhabited worlds, many of which were completely wiped out because Arcot had no knowledge of them, were relieved only when the general call for retreat to protect the mother planet was sent out.