Until the advent of navigational radio, communication with the mainland was spotty. God help the man who broke his leg on the Farallon Islands between the weekly supply-ship visits. But the peril of the European War had meant Crosley crystal-receiver radio sets and quenched spark systems with an eight-hundred-mile range for all who lived and worked on the coastlines, and so, on Sunday, November 12, 1916, just below the Oregon border, at the St. George Reef Lighthouse, eight miles off the California coast, there began an explosion of radio, telephone, and telegraph operations unprecedented in American history.

At high tide, roughly five o’clock in the morning, it was over an hour before dawn. The sweeping eighty-thousand-candlepower light from the third-order lens cast the frothing sea from shore to horizon into the high contrast of white against black for some moments, then back into full pitch-darkness. Two strong men in caps and slickers rowed the station boat toward the crown of stone upon which the lighthouse stood. Their passenger, her corpulent form bundled beneath a treated canvas sail, her arms crossed around her morning pitcher of coffee, was the Second Assistant Keeper, Emily Wheeler. As the light rotated, there was a stroboscopic effect which illuminated her progress cutting across the sea foam that lay like frosting above the crags and crevasses of the ancient reef.

Emily Wheeler, in the third generation of a family of California lighthouse keepers, was a difficult woman, but, as with all difficult women who could demand such isolated work, her desire was immediately granted. Of course, send her to a rock miles off the coastline, go with the governor’s blessings.

But, unlike other such women, she had thought to make her own uniform. She wore it under the sail and her layers of slickers and inflatable vests. It was navy wool, with simple gold braid at the throat, and there was a smart, matching cap under which she tucked the foundry-steel braid of her hair. After considerable thought about stripes—she didn’t want to seem conceited, yet she also wanted to acknowledge her duties—she had given herself the rank of sergeant.

Her lighthouse was the world’s most expensive, nine years in the making, a cylindrical housing hewn from living granite, a 115-foot caisson tower as sturdy as a medieval fortress, its imposing skin interrupted only by the balistrariac slits of loophole windows. And at the very top, capped with iron painted a brilliant red, was its lantern room, in which rotated the Fresnel lens, as faceted as a sultana’s engagement diamond, and which, like the eye of Argus, was chambered myriad ways, as close to omniscience as technology could dare. There was no better light in America.