“In that case I would like to buy you dinner to show my appreciation.”

“Wow! Who says you can’t meet eligible men in the map division? Gotta go. ’Bye.”

Zavala clicked the phone off and made his way to the NUMA helipad. The helicopter was fitted out with pontoons that allowed it to land on water. Zavala gazed at the helicopter lost in thought, then went back to the ship’s bridge.

“I’ve got another favor to ask,” he said.

“We’ll do whatever we can to help,” Captain Campbell said.

“I’ve got a NUMA map expert looking into the history of the atoll the Trouts found the coordinates for. If she comes up with any leads, I’d like to borrow your helicopter to check them out.”

“I’ll make sure it’s fueled and ready to go whenever you need it.”

Zavala thanked Campbell, and went down to the supply shed on the main deck. He had set aside an emergency life raft and was wondering if he needed additional gear when his phone trilled. Beth was calling back.

“I’ve got it!” she said.

“That was fast,” he said.

“Pure luck. I found what I was looking for in the British National Archives. Their stuff is on a database, categorized according to time period. What’s your e-mail address?”

Zavala gave Beth the information, and, before hanging up, made sure he had her personal phone number so he could call to set up a dinner date.

Zavala made his way to the ship’s communications center and borrowed a computer. He called up his e-mail address and seconds later the British Admiralty chart of 1850 filled the screen. He studied the chart for a moment, especially the dot labeled Trouble Island. Then he clicked the mouse. Pacific Chart 2683 appeared.

He put the earlier chart side by side with the corrected one. The circles on the corrected chart designated the position of nonexistent islands that the Admiralty hydrographers had removed. Trouble Island was not circled, but the name had been removed and the dot designated it as an atoll. Some time between 1850 and 1875, Trouble Island had become an atoll.

Zavala made a phone call to a NUMA colleague who specialized in old sailing ships and got an estimated sailing speed for a fully loaded whaler. Zavala then leaned back in his chair, laced his hands behind his head, and put himself in a ship captain’s place.

Song Lee had said that the plague killed within days of infection. The crew would have been in good shape immediately after leaving Pohnpei. He assumed that the ship had a fair wind filling its sails.