As I get closer to the big rock, the little stone in my pocket moves. I make a fist around it and take it out. When I uncurl my fingers, for the second time in a week something jumps from my hand to the rock. The movement of the small pebble is faster and stronger than the magnet. Almost as soon as my hand opens, it’s gone.

Dr. Morgan touches the little stone where it landed on the side of the rock.

“Get up.” Birdie tries to climb onto the big rock. I give her a lift onto the flat part at the top.

“To answer your question, Henry—if I had tried to analyze the composition of my stone, I would have had to grind it up to test in our machines, and break it apart to send pieces to other scientists to corroborate my results. In effect, destroy the stone that came through my window and somehow restored me to health. That is what scientists do, which perhaps makes me not such an exemplary scientist.”

“You are exemplary.” I’m not exactly sure what the word means, but I know it describes Miles Morgan. “You didn’t want a replica of your stone. You wanted to keep the real one. And you would never do this. See the scratches Mr. Ronnie made with his chisel?” I show the curator the marks close to the bottom of the meteorite.

“Not to worry, Henry. I highly doubt they are scratches. See…” Dr. Morgan dips his crisp white pocket handkerchief into the water around the rock and wipes off the silver streaks. There are no scratches.

“Those were merely pieces of Mr. Ronnie’s chisel that the rock wore off,” the curator explains.

“Wow! How did you know the marks would come off?”

“That, Henry, is a question I am not proud to answer. When I was a lad, I borrowed my mother’s favorite ring, without her permission, I must admit. I scraped the little diamond in it across my stone. The only mark that was made was etched right through her diamond, and diamond, as you may know, is a ten on the Mohs hardness scale, much harder than Mr. Ronnie’s chisel.”

“So no one could chisel off a piece of the stone to get the reward, even if they tried?”

“That is correct. Not with any ordinary implements. However, since that first experiment with my mother’s ring, there is one other I’ve been sorely tempted to perform.”

“What’s that?” I ask.

“My team has access to a piece of equipment called a mass spectrometer. We take a sample of a meteorite and vaporize it in the device. It is a complicated process, but it enables us to date the meteorites.”

“You can figure out how old they are?”