Free Fallen Mangrove (Jesse McDermitt Series Book 5) by Wayne Stinnett

clear,” Carl explained. “The solid waste from the fish will fall through the mesh and be siphoned up along with the water as the water’s pumped out of the crawfish tank up into the farm tanks. The crawfish will feed on anything edible in the fish’s waste and break it up, so it can flow more easily through the pumps and bio filters to the plants. The bio filters break the ammonia down into nitrite and then further into nitrate, which the plants thrive on.”
    “Glad you know what you’re doing, Carl,” I said. “It’s all Greek to me.”
    I could hear the sound of an outboard approaching from the southeast. I left them there and went back up to the deck. Looking out beyond Harbor Channel, I could see Rusty’s familiar skiff approaching. He had Deuce with him.
    “Why didn’t Julie come with you?” I asked once we’d tied Rusty’s skiff off to the south dock.
    “She’s nesting,” Rusty said. “Run us off, so she could get their boat cleaned up.”
    “She’s kind of fussy about that,” Deuce said. “Two months of sailing all over the Caribbean has been kind of rough on the interior.”
    We walked up to the deck, then down the back steps and across the clearing. Doc was sitting with Chyrel at one of the tables outside the bunkhouses. We brought Rusty and Deuce up to speed on what was written on the coconut, the translation, and what we thought it all meant.
    “Sounds to me like you guys are goin’ on a treasure hunt,” Rusty said.
    “We have a lot more to find out before we go off looking for anything,” Doc said.
    “I found dozens of geological survey reports dating back to the late 1920s,” Chyrel said. “They contain beach erosion data on Elbow Cay. Using those, along with dozens of early nautical charts, I was able to create a drawing of what the coast line might have looked like four hundred and forty years ago. The island has lost a good three hundred feet of beach. That’s why there are so many exposed rocks along the shoreline. The rock with the house on it was well inland back then, and bigger. The rock that’s now well offshore was on the beach then.”
    Tony gave her the list of things we’d thought of last night, and she disappeared into her little office. She’d printed out many nautical charts of the northern Bahamas dating back to the early 1600s and a history of the islands. The Spanish had had little use for the tiny islands, except to enslave the populace that had once lived and flourished there. By the early 1500s, there were no people on any of the Abacos. Ownership passed back and forth between England and Spain until 1783, when England ceded Florida to Spain in exchange for the Bahamas.
    Doc pointed at the satellite view. “According to the scale, two to three hundred feet west of that rock is quite a ways offshore today.”
    “Early nautical charts were very accurate as far as latitude,” Rusty said. “That’s just a simple matter of shooting the North Star. But determining longitude was still a matter of sailing due east or west and measuring speed to determine distance. Very unreliable”
    He pulled out a chart dated 1728 and placed it next to one dated 1898. “See how wide they show Abaco here and again a hundred and seventy years later?” Before anyone could answer, he placed a modern chart over them, and pointing to the narrow isthmus between the southern end of Abaco and the northern end, he said, “The reality is that the island narrows to just a few yards here.”
    “Okay, what’s your point?” I asked.
    “Even this early map shows Hole Rok, now called Hole in the Wall, at the southern tip of Abaco. Major landmarks for navigation were usually pretty accurate. Life depended on it. This early one shows a rock offshore of Isla Lucayoneque and the reef beyond.”
    “I see what you mean,” Tony said. “If that rock was offshore almost two hundred and eighty years ago, it was probably offshore a hundred and sixty years before that.”
    “I’d bet on