By nightfall of the day after its landing, the door of the ship opened and the explorer came out in a vehicle designed expressly for sampling on this planet. The vehicle came out, stood on its hind legs, closed the door, and piled brush back to hide it. Then it moved away with the easy, feline gait of a mountain-lion. At a distance of two feet it was a mountain-lion. It was a magnificent job of adapting Qul-En engineering to the production of a device which would carry a small-bodied explorer about a strange world without causing remark. The explorer nested in a small cabin occupying the space--in the facsimile lion--that had been occupied by the real lion's lungs. The fur of the duplicate was convincing; its eyes were excellent, housing scanning-cells which could make use of anything from ultraviolet far down into the infra-red. Its claws were retractable and of plastic much stronger and keener than the original lion's claws. It had other equipment, including a weapon against which nothing on this planet could stand, and for zoological sampling it had one remarkable advantage. It had no animal smell; it was all metal and plastics. * * * * * On the first night of its roaming, nothing in particular happened. The explorer became completely familiar with the way the controls of the machine worked. As a machine, of course, it was vastly more powerful than an animal. It could make leaps no mere creature of flesh and blood could duplicate; its balancing devices were admirable; it was, naturally, immune to fatigue. The Qul-En inside it was pleased with the job. That night Antonio and Salazar bedded down their sheep in a natural amphitheatre and Antonio slept heavily, snoring. He was a highly superstitious ancient, so he wore various charms of a quasi-religious nature. Salazar merely turned around three times and went to sleep. But while the man slept soundly, Salazar woke often. Once he waked sharply at a startled squawking among the lambs. He got up and trotted over to make sure that everything was all right, sniffed the air suspiciously. Then he went back, scratched where a flea had bitten him, bit--nibbling--at a place his paws could not reach, and went back to sleep. At midnight he made a clear circle around his flock and went back to slumber with satisfaction. Toward dawn he raised his head suspiciously at the sound of a coyote's howl, but the howl was far away. Salazar dozed until daybreak, when he rose, shook himself, stretched himself elaborately, scratched thoroughly, and was ready for a new day. The man waked, wheezing, and cooked breakfast; it appeared that the normal order of things would go undisturbed.