Limit of Compilation - Sara Wheeler

This tatty map, guarded in its cardboard tube for two decades, takes me back to  one of the happiest moments of my life.  I was in the middle of a seven-month sojourn in the Antarctic, researching a book.  When I used this particular map I was camping in the Transantarctic Mountains close to the Taylor Glacier at about 77 degrees south. I was the guest of an 8-strong American science camp investigating nitrates in the water columns of Lake Bonney. I helped with camp donkey work – spooling rubber tubes into a hole in the ice, dragging water samples on a  Nansen sledge, cooking bread-and-butter pudding with powdered egg. We each had a pup tent for sleeping, and did everything else in a Jamesway – an arched rigid-frame tent heated by a drip-oil Preway burner (the Jamesway was a relic of the Korean war).  A sign above the door said, Good morning scientists! It’s a good day for science!, and an inflatable palm tree  sprouted from the long trestle dining table.  Water samples in test-tubes filled a gas-powered fridge, and food was stored on the floor.

Captain Scott discovered the Taylor Glacier on his first expedition, the one which sailed south in 1901, and he named it for one of his geologists. The  34-mile Taylor lies at the head of an arid valley created by the advances and retreats of glaciers through the Transantarctic Mountains. These dry valleys, partially free of ice for about four million years, are dotted with saltwater basins  and they form one of the most extreme deserts in the world. NASA tested robotic probes there before dispatching them on interplanetary missions: one of the engineers told me, ‘This is as close to Mars as we can get’.  My crew at Lake Bonney, funded by the National Science Foundation, were melting  holes in the twelve-foot lid of ice that covered the lake and lowering sediment traps to the bottom.  It was complex, fraught and expensive work, and shifts regularly  extended through thirty hours straight. Down south it’s hard to keep an ice hole open for three months. The team waged a constant battle against the Big Freeze.  Over supper (usually pasta  with freeze-dried vegetable sauce), the guys – yup, all guys –  talked about the organic carbon sloshing around at the bottom of the lake and the ribboned crystals trapped in the ice cover, and they asked each other questions concerning the microbial life going about its business in the soupy, nitrate-rich water.

One cool February afternoon when I was not needed at camp,  I hiked up the valley, enjoying a clement temperature of five degrees below. There was no wind. I heard  the moat ice cracking on the shore of Lake Bonney and watched the tobacco-yellow plumes of Mount Erebus staining the sky in the distance. The twin peaks of the Quartermains ahead were the only thing that lay between me, the polar plateau, and the South Pole itself, though that was a long way off. Many of the lower slopes of the mountains poking through the ice sheet were ablated with ice, which is rare in the Antarctic. The light was pale as a young lemon.

Fearful of losing my bearings, I stopped to fish this  map from my pack and spread it on the ice. Created by the  United States Geological Survey in the 1980s, it represents that part of the Antarctic continent on a 1:250,000 scale.  Tracing my route by topographical landmarks (including an especially pointy mountain glaciologists had baptized the Doesn’t Matterhorn), my finger came to a zigzag drawn with a ruler marked ‘Limit of Compilation’. I had reached the end of the map. Beyond that, the sheet was blank.

That was where I wanted to be: the end of the map.

Later on that hike, I passed a long-dead seal on the moraine, its wholly intact form coated with mossy green fur. When I told the science team leader later, he said, ‘You are in a place which knows no degradation’. It was the perfect metaphor for the timelessness so often associated with Antarctica. John Priscu (now Professor of Ecology at Montana State University at Bozeman) had already clocked up ten seasons in the Antarctic. Since my visit he has had a valley and a stream officially named for him, like Scott’s Griffith Taylor. Sitting in the Jamesway one bright white night after a punishing day hauling water samples from the lake, he told me he believed the history of the planet was calibrated in the ice.

Since the USGS made this map, satellites have transformed the way we look at the world, and I don’t suppose there is anywhere unmapped today.  My map is part of the past. And contemporary scientists hauling samples from the lakes in the dry valleys use more sophisticated maps. But Antarctica still beats run-of-the-mill cartographers. Search for the Taylor Glacier  on Google Maps. See what I mean?

I like this map for its lack of human spoilage – no cities or highways. Hunched in my office behind a rain-spattered window, London clamoring.  I often unfurl it and trace the glaciers and valleys I once knew so well. But in my dreams, I always stand at the Limit of Compilation.