They went down, over what had been one of that world's largest cities. The air, the stratosphere, and all nearby space were full of battling vessels of all shapes and sizes; ranging from the tremendous globular spaceships of the invaders down to the tiny, one-man jet-fighters of the Arpalones. * * * The Dilipics were using projectile weapons only--ranging in size, with the size of the vessels, from heavy machine guns up to seventy-five-millimeter quick-firing rifles. They were also launching thousands of guided missiles of fantastic speed and of tremendous explosive power. The Arpalones were not using anything solid at all. Each defending vessel, depending upon its type and class, carried from four up to a hundred or so burnished-metal reflectors some four feet in diameter; each with a small black device at its optical center and each pouring out a tight beam of highly effective energy. It was at these reflectors, and particularly at these tiny devices, that the small-arms fire was directed, and the marksmanship of the Dilipics was very good indeed. However, each projector was oscillating irregularly and each fighter-plane was taking evasive action; and, since a few bullet-holes in any reflector did not reduce its efficiency very much, and since the central mechanisms were so small and were moving so erratically, a good three-quarters of the Arpalonian beams were still in action. * * * There was no doubt at all that those beams were highly effective. Invisible for the most part, whenever one struck a Dilipic ship or plane everything in its path flared almost instantly into vapor and the beam glared incandescently, blindingly white or violet or high blue--never anything lower than blue. Almost everything material, that is; for guns, ammunition, and missiles were not affected. They did not even explode. When whatever fabric it was that supported them was blasted away, all such things simply dropped; simply fell through thousands or hundreds of thousands of feet of air to crash unheeded upon whatever happened to be below. The invading task force was arranged in a whirling, swirling, almost cylindrical cone, more or less like an Earthly tornado. The largest vessels were high above the stratosphere; the smallest fighters were hedge-hoppingly close to ground. Each Dilipic unit seemed madly, suicidally determined that nothing would get through that furious wall to interfere with whatever it was that was coming down from space to the ground through--along?--the relatively quiet "eye" of the pseudo-hurricane.