Chapter Twenty Eight
The GPS course plotter placed the Maria Helena twenty miles due west of the Bimini Road. Superimposed on the digital map were three markings which represented the precise location of each of the cargo ships when they were struck by the rogue wave.
Sam put his left hand on Matthew’s shoulder. “This is the place. Take us to a crawl and prepare to commence a circular search of the seabed.”
Matthew carefully eased off the twin throttles. “Copy that.”
The engine vibrations, felt through the steel flooring beneath their feet, ceased and the high pitched roar of the twin diesel engines settled to a dull murmur. Through the large windows on the bridge Sam could see the dark blue water reached the horizon in every direction. The swell was almost entirely flat.
“It’s hard to believe that a place like this has recently sunk two massive cargo ships, caused another one enough damage to render her useful only as scrap metal, and obliterate the Mirabelle — a winner of the Roaring Forties Extreme Circumnavigation!” Sam said.
Next to him, Matthew studied the long range radar and weather reports. The man was meticulous when it came to safety. His eyes then darted from one horizon to the next as though he were expecting a rogue wave to reach them at any moment.
“You okay?” Sam asked.
“Sure,” Matthew replied. “I don’t believe all this rubbish about a rogue wave killing people, but there’s no denying the evidence that something caused these vessels to sink. Whatever was responsible may still be around — and I don’t want to take chances with the Maria Helena and my crew.”
“I understand.” Sam knew that his skipper wasn’t prone to superstition. He was merely being careful. More importantly, Sam realized that Matthew was giving him a warning. “First sign of trouble and we’re out of here.”
“Very good, sir.”
The portside door to the bridge opened. It was Veyron. “The Multibeam Echo Sounder has been deployed. We’re ready to begin the search.”
Sam took two steps to the right where Elise studied the computer aided Digital Terrain Model, which had started to take the first waves of images to build a 3D model of the seabed. “Thank you Veyron.”
The multibeam echo sounders, like other sonar systems, transmit sound energy and analyze the return signal that has bounced off the seafloor or other objects. Multibeam sonars emit sound waves from directly beneath a ship's hull to produce fan-shaped coverage of the seafloor. These systems measure and record the time for the acoustic signal to travel from the transmitter to the seafloor and back to the receiver. Multibeam sonars produce a “swath” of soundings to ensure full coverage of an area. The coverage area on the seafloor is dependent on the depth of the water, typically two to four times the water depth.
“Okay Matthew, let’s commence the circular search.” Sam looked at Elise.
Matthew slowly pushed the twin throttles forward. “Setting the GPS plotted center and commencing circular runs. Are you happy with five knots?”
“Yes.”
Sam studied the 3D imaging of the seabed. It was a new addition to their advanced system of underwater surveying equipment. He was impressed at the quality of the images of over a hundred and twenty feet below the surface.
The seabed was mostly flat and sandy. The shipwreck graveyard that Sam had hoped for certainly wasn’t beneath their keel. If his theory was correct regarding the Antiqui Nautae, this area of seafloor should be riddled with sunken vessels.
The science of discovery beneath the sea was as much an art as it was a testament to a person’s patience. The tedious prospect of working hours upon hours for days and days, staring at nothing but a blank seabed threatened Sam.
It was nearly two hours before they found their first shipwreck.
The monster rose from the seafloor in two, almost identical one hundred and forty-foot-long sections of the hull, in a grotesque image of destruction. Superimposed on the otherwise barren sandy ocean floor the image of the vessel could be seen with such clarity that the ship’s name could be read, indented into the side of the hull — The Argonaut.
Sam took a deep breath. “She was a cargo ship, mostly carrying small digital imports from China. Lost three weeks ago. There was no call for assistance by its crew. She simply disappeared. There was a search, but no one had heard from her since leaving China.”
Tom stared at the hull. It looked more like it had been hit by a torpedo. “Now we know what happened.”
“All right, let’s GPS mark the final location of the Argonaut. Her owners will want to know what happened to her,” Sam said.
“Do you want me to make another circuit so you can get a better look at her?” Matthew asked.
“No thank you.” Sam made a note on his navigational chart of the precise location of the Argonaut. “Let’s continue with the search grid. If I’m right, we should find some much older ships down here.”
Matthew pushed the throttle halfway forward again. The Maria Helena picked up speed. “Copy that Sam.”
By the end of daylight, the other two cargo vessels — the Tahila and the Arkansas — had been found, but no sign of any older shipwrecks were spotted.
“That’s the end of the sunlight,” Matthew said. “We’ve covered a five-mile radius from the known location where the Tahila was struck. What do you want to do?”
Sam studied the circular grid of area they’d surveyed. It was extensive. They’d covered a lot of ground. He then looked at the 3D mapping that Elise was working on. “We’ll continue through the night. Break into four hour shifts with teams of two. Right now all we have is my theory and the fact that something keeps sinking large cargo ships in the area. If we don’t work out what that is and stop it, shipping in the region is going to grind to a halt.”
Tom looked at the navigational charts. “Where do you want to search? We’ve already covered any reasonable area close to the site of the rogue waves. What makes you so certain that we’ll find these 17th century shipwrecks?”
“Because I just realized my calculations were so far off. The cargo ships were nearly three hundred feet long!”
“Of course!” Veyron was the next to understand it. “At that size the ships would be dragged much further than the 17th century schooners and Man o’Wars.”
“Meaning?” Tom asked.
“The 17th century vessels will be further back towards the Bimini Road.”
Chapter Twenty Nine
The Maria Helena headed east again. The ground below became empty and the seabed devoid of all but natural sea life. It never ceased to amaze Sam that below the vast ocean laid an empty and monotonous world. Few changes in the sandy bottom were seen over a number of miles.
And then the Swath began to highlight a manmade object. It was much smaller than the previous ones, almost as though most of it was already buried. Perhaps by four centuries of sand and debris.
Then another one came into view.
Followed by a third and fourth.
“My God!” Matthew said reverently.
“Gentlemen, I think we’ve just come across the hunting ground of the Antiqui Nautae.”
A fifth shipwreck came into view. This one appeared much larger than the previous ships in the area. “Veyron, can we increase the clarity of that image?” Sam asked.
Veyron ran tapped the keyboard and a grey wave crossed the monitor screen, increasing its clarity. By the third attempt the image became clear. “What do you think about that?”
Tom sighed as the image came into clear view.
In front of him stood the perfect outline of a British Man-O-War.