I divide volcanoes — and their craters — into two types, hot and cold. Galeras falls into the cold category, which has its own mix of discomforts. Chief among them are the thin air and the frequent shifting between overheating and freezing as you sweat during the ascent, then shiver when the sun disappears behind clouds and you work at high elevations. With hot, lower-altitude volcanoes, such as those in Costa Rica and Nicaragua, you sweat all the time, your clothes stiffening from the salt when they dry. Nearly all craters are awash with acidic gases so strong they can corrode the metal eyelets on your boots and leave your skin feeling as if it has been rubbed raw with Brillo pads.
That afternoon on Galeras, steam clouds often obscured my friend Igor Menyailov, a highly regarded Russian volcanologist who was sitting amid a jumble of rocks thrusting a glass tube into a fumarole. From deep inside the earth, gases streamed out of the vent at 440 degrees Fahrenheit and bubbled into solution in Igor's double-chambered collection bottle. Taken over time, these samples of sulfur and chlorine might reveal the volcano's secrets. Was the magma body rising? Was an eruption imminent? It was Igor's first time on Galeras, his first time in South America, so he could tell little about this particular mountain yet. But the fifty-six-year-old Russian — a short, handsome man who learned English by listening to black market recordings of Elvis Presley -- looked content, smiling, smoking a cigarette, swiveling his head away from the shifting gas clouds as he talked with the Colombian scientist Nestor García.
Circling the rim of the crater, appearing and reappearing in the fog like a phantom, was the English volcanologist Geoff Brown, accompanied by the Colombian scientists Fernando Cuenca and Carlos Trujillo. Brown, a rangy, affable man who also had never set foot on Galeras till now, was taking the volcano's pulse with a sophisticated contraption called a gravimeter. One hundred million times more sensitive than a grocer's scale, the gravimeter gauges the forces of gravity on a mountain as it heaves under the power of rising, molten rock. Geoff was trying to map the innards of Galeras, hoping, like Igor, to determine if magma was on the move or if an eruption was likely. We all used different methods, but our goal was the same — to understand what makes a volcano tick, to forecast eruptions, to save lives. We all wanted to save lives.
I know now what a tricky and elusive thing memory can be, particularly after a calamity such as Galeras. I sustained a grave head wound, but was nevertheless able to piece together a picture of the last minutes before the eruption. Over the years, as I underwent sixteen operations, as Galeras greeted me every morning when I awoke, as I slogged through a recovery that continues to this day, I came to believe unshakably in my version of what had transpired on the crater rim before Galeras blew. But I am less certain now. Three of my colleagues, standing just feet from me, remember things differently. Are they right? Can their stories really be true? Some of my memories are vivid, others less so. But no matter. This is what I remember of the moments before Galeras exploded. About the eruption itself — well, we're all more or less in agreement on that.