And the way to find out what tomorrow would bring, of course, was to wait for tomorrow.
The next day at lunch, Jon sat down with Karyn and conversation quickly turned to the subject of the rock.
"It just is so overwhelming," said Karyn. "You could do anything with this rock... Say, I have an idea!"
"You have an idea?" wondered Jon.
"Yes, I just said that! You know, I always wanted to visit some foreign countries. Why don't you use the rock to take us to, umm... Italy for lunch?"
"I can't. It has a range. But maybe I can wish up some airline tickets."
"Naah," said Karyn. "Then we couldn't just go there for a few minutes, the trip would take hours and we'd have to explain it to everyone. But I just got an even better idea..."
"Karyn," said Jon. "You have that look on your face... please tell me it's not something I'll regret."
"Nothing like that at all, Jon! How about time travel? Go a few years back and we can see what Sarah was like in grade school. Go decades back and we can meet our parents in school. Go a little more back and we might be able to visit a Beatles concert. Go farther back and even if nothing special happens, it's so different it's like visiting another place anyway...."
Jon held up a hand. "Stop." he said. "Karyn, I can't do that either. We can't reverse wishes, which means we'd be stuck wherever we went."
"I bet you won't" said Karyn. She reached for Jon's other hand and poked her finger at the stone, while making a wish. "I wish" she said, "that me and Jon know if wishes like that really can't be reversed."
"I don't think that worked" said Jon. "I don't hear any voice in my mind...." Hey, my soup!
Jon's bowl of alphabet soup was beginning to swirl, as if someone invisible were stirring it. Noodle letters floated to the surface and spelled out sentences against the orange liquid.
Jon and Karyn looked a little silly both leaning over the same bowl of soup, but they made out the message: "After a wish to travel and a second wish to travel, both travels have happened. Therefore, the second wish is not a reversal of the first even if it sends the wisher back where he came from."
"That's it!" said Karyn. "We can do it."
"I don't know" said Jon. "Maybe we should test it first."
Karyn took the stone and said "Okay. I wish that me and Jon travelled two days into the past."
Two days in the past was a Sunday. After feeling the usual sensation of a wish being made, Jon noticed that it was dark. And quiet. They were sitting in the same room, but it was completely deserted.
"Yay!" said Karyn. "It worked!"
They got up and walked around the building a little bit. It was strange for the building to be empty when they had been in class just a few minutes ago.
"Hey, look, there's my locker" said Karyn. I don't start coming here until tomorrow. I wonder if I can leave myself a message?"
Karyn tore a piece of paper out of her notebook and wrote on it, "Don't wish for blonde hair. Wish for brown hair." She stuffed it through the crack under the locker door. Then she made the wish: "I wish that me and Jon were back in our own time, at the exact moment we left."
And instantly, it was done.
Karyn looked around for someone she knew. The first person she spotted was the math teacher. She waved her down and asked, "Excuse me, Mrs. Roberts what do you think of my hair?"
The woman looked at Karyn's hair and thought a moment, then replied "It looks quite attractive, better than when it was brown. Did you bleach it?"
"Sort of. And thanks!" said Karyn.
As the teacher walked away, Karyn handed the stone back to Jon. "I think we've tested enough," she said. "We know it works and we know we can return. And we can change the past. Instead of wishing for blonde, I wished for brown, so Mrs. Roberts thought I had brown hair. But we're not affected by any changes we make while we're in the past--my hair is still blonde. So it's okay, if we're careful not to change too much. We can go!"
"But we have class once lunch is over" said Jon.
"That's okay, we can be gone as long as we want and come back to the same moment."
"So where do you want to go?" asked Jon. "Find Sarah when she was six years old and change her to a boy?"
"No, if I wanted to do that we could just change her right now. I'll tell you as soon as we put our books and papers away. You wouldn't want to be going sightseeing with all these books, would you?"
"Hmm, I guess not."
They went to their lockers and put their stuff away. Then Karyn handed the stone to Jon. He handed it back, saying "You do it."
"Sure, Jon" said Karyn, holding the stone in her hand. "I wish for me and Jon to travel through time to...."
