The men started on a run. Lamoureux, waiting impatiently, walked up and down in growing excitement. He had come prepared for a three months' search, expected it. He had pictured himself and his men, exhausted by a long trek across the planet, coming upon the startled Kalinoff, striking a magnificent attitude, and saying, with characteristic Tellurian modesty, "Dr. Livingston, I presume." And, instead, he was going to find Kalinoff in less than a day. He ran into the ship, got out the printed contract, and read it hastily. All was in order. He'd have Kalinoff's signature that day. A half hour passed, and Lamoureux fired ten more shots. Haskell, the cook, was looking at the sky with a troubled expression on his face. He approached Lamoureux apologetically. "Say, Captain--" "What is it, Haskell?" "Does it ever rain on Mercury?" "Never. No rain, no snow, no hail. No man who has ever set foot on the planet has come across any sort of bad weather. Kalinoff emphasizes that fact." "Well, that's what I seemed to remember. But just now I thought I felt a drop of rain." "Impossible, Haskell. Some bird--" Lamoureux stopped abruptly. He, too, had thought he felt a drop of rain. Haskell held out a hairy paw. "I thought I felt another one." His eyes fell on the brown rocks. "Say, here's a big drop that splashed." The brown rocks were being slowly spotted with black. And, as Lamoureux stared, he felt his head grow wet. There was no doubt about it. It was raining. His mouth dropped open. "But it doesn't rain on Mercury!" The sky was a dull gray now, and the patter of rain drowned out his words. He realized suddenly that he was becoming soaked. Haskell was running for the ship. Lamoureux followed him and slammed the door shut. The men who had not been sent to search for Kalinoff were already inside. The rain rattled on the hull of the _Astrolight_, and on the parched ground. Lamoureux stared through the side port and repeated blankly, "But it doesn't rain on Mercury!" Fortunately, the noise of the rain was so loud that no one heard him say it. II It was six hours before the first of the search parties Lamoureux had sent out returned. The men were soaked, but they had seen no trace of Kalinoff. They had faithfully tried to follow Lamoureux's directions, but in a downpour where it was impossible to see more than fifty feet ahead of them, they stood little chance of rescuing anyone. Most of the six hours had been spent finding their own way home. The other search parties drifted in slowly, until all had returned. Lamoureux checked them off one by one, and discovered, with practically no surprise, that McCracken was missing. "Where is the idiot?" he growled. "McCracken separated from the rest of us," replied Carvalho. "He thought he could catch a glimpse of those mountains Kalinoff described." "When was this?" "Just before it started to rain."