Gop flushed. A member of the Transverse Colon Revivalists, he found Pud's constant atheistic swearing very disturbing. He sighed inwardly. Usually at least one of Pud's heads could manage to keep its sense of humor, but right now all of them were like proton-storms. The Senior Scientist was on the verge of one of his totalitantrums. "They must have sighted flashes from our experiments," Pud went on, "before you decided you could spare just _one_ set of eyes for the Detector!" * * * * * Though both Vegans were invisible to other eyes, they remained visible to each other because their eyes were adjusted to the wavelength of their invisibility fields. By the same token, they could see all their invisible experiments--a vast litter of gadgets, gismos, gargantuan gimmicks, shining tools, huge and infinitesimal instruments, stacks of supplies, and various types of energy fields, the latter all frozen in mid-activity like smudges on a pane of glass. The sandy ground was the floor of the Vegans' laboratory; small hills and outcroppings of rock were their chairs and work-benches. Like a spaceship junkyard, or an enormous open-air machinery warehouse, the laboratory stretched away from the two Scientists in every direction to the planetoid's near horizon. Pud intensified the general invisibility field to the last notch, and the invisible experiments became even more invisible. The _thig_-field was a nameless-colored whorl of energy in the Senior Scientist's tentacles. In his concern for the other experiments, he had forgotten to deactivate it. It grew eagerly to the size of a back yard, then of a baseball diamond, then of a traffic oval, and one shimmering edge of it touched his body, which he had not insulated. Energy crackled. Pud jumped forty feet into the air, swearing, and slapped the field into non-existence between two tentacles. His body, big as an apartment house, floated slowly downward in the laboratory-planet's light gravity. The tiny alien spaceship touched the ground just as he did. The rocket flare flickered and died. The ship sat on its fins, about thirty feet--Vegan feet--away. In its shining side, a few Vegan inches above the still smoking rocket tubes, was a small black hole. "Master, look!" Gop thought. "Their ship is damaged ... perhaps that's why they landed!" And he started to extend a tentative extra-sensory probe through the hole. Pud lashed out with a probe of his own, knocking Gop's aside before it could enter the hole. "Nincompoop! ... don't go esprobing until we know if they're sensitive to it or not! Can't you remember the regulations on Contact for just one _minute_?" The tiny spaceship sat silently, while its occupants evidently studied the lay of the land. Small turrets halfway up its sides twitched this way and that, pointing popgun armament.