Following an anchor rope straight down into the cold, green Pacific Ocean, Bob Schmieder swam toward his personal El Dorado in the fall of 1978.
Schmieder, then a Bay Area research physicist and recreational scuba diver, had plotted every detail of his dive on Cordell Bank, an underwater mountain wrapped in mystery, not gold.
Strobe lights were fixed every 10 feet to the rope, enabling Schmieder, 37, and his fellow divers to keep it in sight during their 120-foot descent.
A diver who drifted away from the line could easily become lost and confused — especially under the intoxicating grip of nitrogen narcosis — and perish in the 50-degree water about 25 miles offshore from Bodega Bay.
About 70 feet down, Schmieder encountered a dark mass that momentarily crushed his spirit as he mistook it for a featureless ocean bottom.
It was instead a dense school of fish that parted as Schmieder flippered through it.
"It was just like opening a curtain," he said, recalling a scene still fresh in his mind 35 years later. "The whole view exploded in front of us."
Schmieder, now 71 and retired, had descended right on target, next to a 200-foot-wide pinnacle at the south end of Cordell Bank, a huge chunk of granite resting at the edge of the continental shelf, where the seafloor abruptly plunges from about 400 feet to the 6,000-foot abyss.
The date was Oct. 20, 1978, coincidentally 125 years to the day since Cordell Bank was discovered, accidentally, by a surveyor named George Davidson in 1853. The shoal, marked on charts, was well known to mariners but to Schmieder's knowledge had never been seen by the human eye.
Corals, sponges, anemone and sea stars blanketed the rocky outcrops, with swarms of rockfish circulating overhead. Natural hues of red, yellow, green, blue, purple and white gleamed in water of tropical clarity, with about 80 feet of visibility.