How to Time Travel

It was best to keep Karyn in the loop, so Jon showed her the letter and got some feedback from her. "So, do you think I should use the stone to go back in time?" Jon asked. "To when? The letter doesn't say. For all *you* know you were an old man when you wrote this." Jon hadn't thought of that. "Then what should we do?" "Maybe you aren't supposed to use the stone to go back into the past. Maybe you do it by some other way." "Like what? I don't see any DeLoreans around," Jon said. "Ha, ha. Very funny. But maybe there really *is* a time machine around somewhere. Or maybe you could wish one up." "Isn't that the same as using the stone to travel through time?" "I don't know." Jon and Karyn sat in the bedroom thinking of a plan. And an hour later, they came up with one ...