I stared at the thing, puzzled. A few hundred years ago the fabled surface-ship pirates of Earth's romantic sea-history supposedly made maps like this. Maps of buried treasure. Pirates' gold. Were Carson and his young sister after some treasure? Where? On Earth? Mars? Little Deimos? Asteroid-9? That thought leaped at me. Certainly they had shown a queer interest in my chance remark about Asteroid-9. We were not far from it now. Fifty thousand miles perhaps--would pass at our closest point to it in an hour of two. I stared through the bull's-eye beside me. It was down there, diagonally ahead of us--a full-round, putty-colored disk, with the configurations of its mountains and the turgid clouds of its atmosphere beginning to be visible. But what could any of that have to do with the Phantom raider, or the attack on the patrolship and the impending attack upon us? Surely there was no treasure on Asteroid-9. The treasure, if you could call it that, was right here on board the little _Seven Stars_. I was crouching now in the shadow of the loading engine on the bow-peak, puzzled by my rush of thoughts. Should I take this to Captain Wilkes? Vaguely I realized that perhaps I should, but something stopped me. My own instinctive feelings for Brenda Carson. She seemed somehow so pathetic. Surely she was no plotting murderess. Her brother--yes. But the girl--protecting someone she loved? Was her father really the Phantom raider? His invention an X-flyer endowed with mechanical, electronic invisibility? I knew that such a thing was scientifically possible, of course. But Professor Carson was a frail old man. And my mind leaped back to some other things Chief Rankin had told me. The Phantom was thought to be a notorious Earth-criminal who, a few years ago, had been known as the "Chameleon." A fellow skilled in the art of wax disguise so that none of the Earth crime-trackers really knew what he looked like. He was wanted in both Great New York and Great London for mail-tube murders. Nothing was known of his identity save that he had once had an operation for a fractured skull, where in the back of the skull a big triangular platinum plate had been inserted to take the place of the shattered bone. A criminal surgeon, dying, had confessed that much; had said he had performed the operation. And then he had mumbled something about the Chameleon being the Phantom raider. Surely such a notorious skilled adventurer could not be old Professor Carson. I decided not to have Brenda and Philip hauled before the captain now for questioning. * * * * *