By then, there were thousands of doctors treating the war’s wounded and ill. Among them was a seventy-one-year-old Scottish surgeon, Alexander Ogston, who decades earlier had discovered and named Staphylococcus.

Ogston was a huge fan of Joseph Lister, whose observations about postsurgical infection led to the use of carbolic acid and other sterilization techniques. These drastically increased surgical survival rates. Ogston wrote to Lister in 1883, “You have changed surgery . . . from being a hazardous lottery into a safe and soundly based science,” which was only a bit of an exaggeration. Before antiseptics, Ogston wrote, “After every operation we used to await with trembling the dreaded third day, when sepsis set in.” One of Ogston’s colleagues, a nurse who worked with him at the Aberdeen Royal Infirmary, declined surgery for a strangulated hernia, choosing death, “for she had never seen a case which was operated on recover.”

After visiting Lister and observing complex knee surgeries healing without infection, Ogston returned to the hospital in Aberdeen and tore down the sign above the operating room that read, “Prepare to meet thy God.” No longer would surgery be a last-ditch, desperate effort.

Ogston was so obsessed with Lister’s carbolic acid spray that his students wrote a poem about it, which reads in part:

And we learned the thing of the future

Was using unlimited spray.

The spray, the spray, the antiseptic spray

A.O. would shower it morning, night and day

For every sort of scratch

Where others would attach

A sticking plaster patch

He gave the spray.

Ogston’s first wife, Mary Jane, died after childbirth a few years before these revelations, at the age of twenty-five. There’s no record of her cause of death, but most maternal deaths at the time were caused by postpartum infection, often due to Staphylococcus aureus. And Ogston had seen hundreds of his patients die of postsurgical infection.

No wonder, then, that he was obsessed with antiseptic protocols. Still, he wanted to understand not just how to prevent infection, but also what precisely was causing it. By the late 1870s, many discoveries were being made by surgeons and researchers about various bacteria and their role in infection, but Staphylococcus was not identified until Ogston lanced a pus-filled, abscessed leg wound belonging to one James Davidson.

Under the microscope, Davidson’s abscess was brimming with life. Ogston wrote, “My delight may be conceived when there were revealed to me beautiful tangles, tufts and chains of round organisms in great numbers.”

Ogston named these tufts and chains Staphylococcus, from the Greek word for bunches of grapes. And they do often look like grape bunches—plump spheres gathered together in tight clusters. But Ogston wasn’t content with just seeing bacteria. “Obviously,” he wrote, “the first step to be taken was to make sure the organisms found in Mr. Davidson’s pus were not there by chance.” So Ogston set up a laboratory in the shed behind his home and began trying to grow colonies of staph, eventually succeeding by using a chicken egg as the medium. He then injected the bacteria into guinea pigs and mice, which became violently ill. Ogston also noted that Staphylococcus seemed to be “harmless on the surface” despite being “so deleterious when injected.” I have also observed this—insofar as I am not much bothered by having my skin colonized by Staphylococcus aureus but find it deleterious indeed when it starts replicating inside my eye socket.