Spencer had mentioned a rusticle growing inside the Britannic that seemed different from the rusticles growing more than two miles deeper at the Titanic. This had puzzled the microbiologists, but there was nothing more exciting to true seekers than a new puzzle to be solved.
Only days after a platform was placed atop the port side of the Britannic’s promenade deck, just behind the fourth window, cameras revealed evidence of rusticles already taking root on the platform’s steel plates (called coupons). During his May 25, 2008, dive to the Britannic, Spencer sent the rusticle platform up to the surface for analysis after five years on the promenade. The results were not quite what anyone expected.
Cullimore’s metabolic tracking system revealed that the chief instigator of the nearly 29 percent steel loss on the test platform involved at least five different types of bacteria working together in distinct layers of an almost perfectly familiar, rusticlelike consortium: (1) extremely active, acid-producing bacteria, (2) very active species that produced protective slime layers over the consortium, (3) moderately active iron-oxidizing bacteria, (4) moderately active nitrogen-metabolizing bacteria, and (5) a lower layer of bacteria that mined (or dissolved) iron in the absence of oxygen. No primitive, hydrothermal sulfur-loving bacteria were detected in the Britannic’s test platform, as had been detected in the Titanic’s rusticle reef; nor were photosynthetic algae signatures found on or in the Britannic platform.
Although it was only a preliminary result, the indications were perplexing. The Britannic’s rusticle consortium was very different from the one presently turning more and more of the Titanic’s inorganic hull and deck plates and deep-ocean nutrients into its own DNA and skeletal structure. The Britannic rusticles also appeared to be more aggressive. They quickly doubled the surface area available for the mining of iron by dissolving pathways into microfolds made in the steel during the rolling process of manufacture. They were experts at bio-wedging the folds open.
The Titanic’s test plates were losing an average of 1.7 percent of their iron per year. The Titanic’s rusticle shroud attacked bent or stressed steel almost twice as fast as it attacked unstressed steel, which was consistent with the much greater deterioration of the areas near and behind the down-blasted gymnasium and with the year-by-year collapse of the even more intensely ravaged stern section.
The Britannic’s test plates were losing approximately 5 percent of their iron per year, yet the Britannic’s rusticles did not exhibit a greater efficiency at attacking bent or stressed steel coupons—which seemed consistent with the randomly distributed rusticle hot spots on and in the Britannic.
No one knew how long the rusticles had been colonizing the Britannic. A recent invasion was implied, for if the 5 percent per year decay process of the nearly six-year-old platform was an accurate indicator of what had been happening to the Britannic all along—at a rate more than twice that of the Titanic—the entire structure should have collapsed into pieces of steel plates by 1960 and been converted into a molasseslike mass of iron ore studded with glass and porcelain artifacts long before Chatterton became infected. The implication was that something in the Britannic’s environment had been changing in the relatively recent past and that the Britannic itself would, within a decade or so, be subject to rather sudden collapse as its steel ribs weakened to such extent that they could no longer support the weight of the hull. Something was causing accelerated rusticle growth on the bottom of the Atlantic, and it appeared that something very similar was happening in the Mediterranean. Deep-water environments were undergoing recent and dramatic change, and some of the scientists were getting a little scared.
In May 2008, the microbiology team had recovered three rusticle test platforms from the Titanic and one from the Britannic, along with an emerging database from DKM Bismarck, DKM U-166, and several ships sunk during World War II in the Gulf of Mexico. The results were consistent with the warning of a sea change, first recorded in the Titanic’s rusticles.
Spencer was helping to expand the Britannic’s database. On May 25, 2008, he planted Cullimore’s newer, improved General Underwater Coupon Corrosion Installation (GUCCI) platform. The sending up of the old platform and the planting of the new platform on the Britannic’s hull turned out to be two of the last things Spencer ever did.
After setting the GUCCI rack and two new bacterial etching experiments in place, Spencer still had a few minutes remaining to himself before he needed to begin the slow, carefully staged ascent to the support ship. Like Parks Stephenson, he was intrigued by the intact Marconi shack, but the extra minutes to explore its interior had not been available before.
He was, at that time, using a new rebreather system. As part of a pre-ascent safety check, Spencer was in the process of changing to a fresh set of tanks when something went terribly wrong near the Marconi shack. The new system gave him too strong a burst of oxygen—which, at that depth, sent him immediately into convulsions. Two safety divers tried to assist him by adjusting the mixture, but the convulsions only worsened, so a decision was made to propel him to the surface in an emergency ascent that would miss all of the scheduled decompression stops.
Preparations had already been made for a situation such as this. In this case, contingency ascent meant that were there not a hyperbaric chamber aboard the support ship, dissolved oxygen and other gases in Spencer’s blood would—within a minute of his reaching the surface and taking his first breaths—begin to expand like foam in a freshly opened bottle of beer, throughout every capillary in his body, from his big toe to his frontal lobes. As in the classic film 2001: A Space Odyssey (in which an astronaut is thrust briefly into a vacuum), there was time to avoid boiling blood and the bends as long as the original high-pressure atmosphere he had been breathing was quickly restored.
Fortunately, the National Geographic support ship was equipped with a portable hyperbaric chamber, in which Spencer was immediately restored to an atmospheric pressure equivalent to what he had been breathing three hundred feet under the sea. The entire chamber was then flown by helicopter to the Athens naval hospital, but Spencer never regained consciousness, and there was no way to revive him.
It weighed heavily on Lori Johnston that Spencer had been placing hers and Roy Cullimore’s equipment minutes before the accident occurred. “I have guilt and deep sorrow for Carl’s loss,” Johnston wrote to a friend. From the moment she had met Spencer, just before his first Mir-2 dive to the Titanic in 2003, they had become fast and close friends and had begun plotting new scientific adventures on and under the high seas. Their next adventure quickly followed: the 2003 Britannic expedition, during which the first test platform was planted.