The map and Dr. Silva’s notebooks looked complicated, but Jacob forced himself to sit down and go through each page. After an hour or so, he checked his watch. He would have to hurry. If he wasn’t back by dinner, John might come looking for him. Fortunately, he found the concept quite simple, once he saw the pattern.
The tree accessed power connected to the longitude and latitude of the Earth, like a spider on a web. The web connected the tree in Paris to the place the spider crawled. The spider moved around the globe at an angle, reaching every other tree in the world over the course of a year. Over twenty-four hours it moved along the longitude of the Earth. At the same time, the months of the year caused it to climb the lines of latitude. The power reached the equator halfway through the year, which was why, he realized, they had visited Peru in June.
The calculation of longitude was fairly straightforward, mapping exactly against the time zones and International Date Line. Latitude was much trickier. The rise from South to North happened more quickly at the poles and slowed as the force reached the equator. He thought of it like this: the spider’s web was stretched more tightly across the middle of the Earth and the spider had longer to crawl to complete the circle to reach its next thread.
He smoothed the map out on the desk and searched for the North Pacific just beneath the Tropic of Cancer. When he’d found Oahu, he traced it with his finger. The island was small in the vast blue ink that represented the Pacific Ocean. If he didn’t know exactly what he was doing, he could easily drown in its depths, emerging in a mass of seaweed, miles from dry land. Of course, he could control water now. If he missed, he could ride a wave to shore—he hoped. A date near the island read August 15th, 1992. It was logical that August 15th would be the date he tried to get home to find his mother.
He thought he understood the basics, but there were things he couldn’t explain, anomalies that didn’t follow the rules, like a rogue date in Munich, Germany in January 1945, and Hong Kong in December of 2000. Dr. Silva said it had taken her decades to learn to use the tree. Jacob only had a few minutes more. As luck would have it, he found the answer in her journal.
Dr. Silva could use sorcery to build a string between Oswald and any other tree, regardless of the date. Her power acted as the tree’s power; she stood in for the spider. But following the string backward from a normal tree was only possible while the string was still open, twenty-four to forty-eight hours. According to Dr. Silva’s earliest entries, climbing back up the spider’s web always took magic. She could follow someone or something else, if their string was still open. But once the string was gone, a normal tree wasn’t enough to amplify her magic.
No wonder she had been so adamant about Jacob not using the tree alone. Without her, there was no way he could get back. It also explained why their trip to Peru had to be short. She needed to help him return before the string dissolved.
Jacob slapped his hand on the desk when he realized Dr. Silva could’ve used her magic to take him to visit the Medicine woman much earlier. What she’d told him had been a half-truth. Yes, if he were traveling alone, June 10th was the day of connection. Dr. Silva could’ve built a string from Oswald. He suspected she hadn’t offered because she knew the trip wouldn’t help. She wanted to dangle the carrot long enough to fill his head with her story about being a Soulkeeper. He’d been such a fool.
The trip to Oahu would be risky. He wouldn’t have Dr. Silva to help him back. If he went through with this, it would be permanent. But after everything he’d learned this week about Dr. Silva’s half-truths and the Laudner family history, he didn’t care. He had to go.
He rolled the map and tucked it back into the corner of the shelf. With the help of some notes he’d made, he replaced the notebooks exactly how they’d been. Dr. Silva was returning the day after tomorrow and it was imperative that she not know what he was planning. He folded his page of notes and slid it into his back pocket.
Making his way toward the stairs, the ruddy cat seemed to pop up out of the floor at Jacob’s feet, and he stumbled trying not to kick him. Gideon was statuesque, staring out the window. On a whim, Jacob decided to throw him off the trail, just in case he changed his mind about being helpful.
“Thanks, Gideon. I guess my plan won’t work after all. Not without Dr. Silva anyway. I wouldn’t be able to get back. But thanks for giving me a chance. Now I feel like I’ve done what I can.”
The cat’s eyes wrinkled at the corners and he wondered if Gideon knew he was lying. He walked down from the tower side by side with the cat. Before he left, he saw Gideon eating. That was all the assurance he needed.