THE MOONS OF MARS By DEAN EVANS Illustrated by WILLER [Transcriber's Note: This etext was produced from Galaxy Science Fiction September 1952. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] Every boy should be able to whistle, except, of course, Martians. But this one did! He seemed a very little boy to be carrying so large a butterfly net. He swung it in his chubby right fist as he walked, and at first glance you couldn't be sure if he were carrying it, or it carrying _him_. He came whistling. All little boys whistle. To little boys, whistling is as natural as breathing. However, there was something peculiar about this particular little boy's whistling. Or, rather, there were two things peculiar, but each was related to the other. The first was that he was a Martian little boy. You could be very sure of that, for Earth little boys have earlobes while Martian little boys do not--and he most certainly didn't. The second was the tune he whistled--a somehow familiar tune, but one which I should have thought not very appealing to a little boy. "Hi, there," I said when he came near enough. "What's that you're whistling?" He stopped whistling and he stopped walking, both at the same time, as though he had pulled a switch or turned a tap that shut them off. Then he lifted his little head and stared up into my eyes. "'The Calm'," he said in a sober, little-boy voice. "The _what_?" I asked. "From the William Tell Overture," he explained, still looking up at me. He said it deadpan, and his wide brown eyes never once batted. "Oh," I said. "And where did you learn that?" "My mother taught me." I blinked at him. He didn't blink back. His round little face still held no expression, but if it had, I knew it would have matched the title of the tune he whistled. "You whistle very well," I told him. That pleased him. His eyes lit up and an almost-smile flirted with the corners of his small mouth. He nodded grave agreement. "Been after butterflies, I see. I'll bet you didn't get any. This is the wrong season." The light in his eyes snapped off. "Well, good-by," he said abruptly and very relevantly. "Good-by," I said. His whistling and his walking started up again in the same spot where they had left off. I mean the note he resumed on was the note which followed the one interrupted; and the step he took was with the left foot, which was the one he would have used if I hadn't stopped him. I followed him with my eyes. An unusual little boy. A most precisely _mechanical_ little boy. When he was almost out of sight, I took off after him, wondering.