new student paled at the prospect of more calculations. “Latitude can be found by simply measuring the angle of Polaris above the horizon. The North Star is always over the North Pole no matter where in the world it is viewed from. The earth spins and swings like a ball on string suspended from Polaris and is therefore constant among the rush of stars travelling from east to west across the night sky. At dusk or dawn, when the horizon can still be seen in the dim light and Polaris is visible in the murk of the transitional sky, the angle read on the sextant is almost equal to the latitude on which the observer is standing. Some corrections have to be applied to get the exact latitude, but a very convenient method nonetheless.”
The next morning, David and the men of the post heaved the last few shovels of frozen earth onto the fresh mound that covered Mr. Hudson’s shallow grave behind the storehouse. Hudson, Turnor’s assistant, had been sick when their canoes arrived, and he had grown progressively weaker until finally the unknown ailment took the assistant’s life. That evening, David returned to his quarters and began practising refraction calculations, partly to forget about Hudson’s death. The grave could have easily been his own just a few months earlier. But he also studied to ready himself. Turnor would need a new assistant.
Accidental? David wondered. A circumstance of birth sent me to Grey Coat where it was predetermined that I study mathematics and navigation. An unavoidable injury suffered in the wilderness fated me to study under a famous astronomer. Now Hudson’s death means Mr. Turnor needs an assistant. Maybe I was never supposed to navigate a ship but was meant to be a map-maker and chart unexplored lands.
The prospect of being able to help map the vast unknown like the famous Captain Cook kept David studying under a flickering candle late into the winter nights. By winter’s end David’s eyes were inflamed from working under dim light. Still, he drove himself until Turnor made ready to leave Cumberland House for his mapping expedition. By that time David was near blindness, weakened by an infection, and unfit to go. He was forced to stay behind while Peter Fiddler, another young clerk, took his place at Turnor’s side.
Before Turnor left, he called David aside. “So, young man,” he said, “Do me a favour. Don’t try so hard next time. They tell me you’re being sent back to York Factory as soon as your eyesight recovers. Your leg has healed nicely so I’ve sent a letter to the factor recommending you as a surveyor. Keep faith that your time will come. And use this,” said Turnor, handing David a brass sextant. “The radius is small but it was made by Peter Dolland, one of the finest makers in England. You can use it ’til we meet at York Factory next year. All the best, Mr. Thompson,” the astronomer said, handing David the sextant’s storage box.
Turnor’s party shoved off, leaving David standing at the lake’s rocky shore with his dreams held in that small wooden box. One day, he hoped, the Company might ask him to cross the mountain range to the west. Then, when one of the creek beds he’d been following for days dwindled to nothing and it was the end of some river and the edge of nowhere, he’d make his own map and his own choices. Maybe the company would tell him to push west, but only he could decide whether to first go northward or south. He’d be the one to choose whether to follow some untravelled valley and hope to pick up the beginnings of a new river or perhaps crest some distant ridge into another drainage. Whatever his choices, right or wrong, he could trust the stars and his sextant, and they would help him show others where he had gone.
“June 9th, 1790 – Cumberland House – north latitude 53 degrees, 56 minutes and 44 seconds; west longitude 102 degrees and 13 minutes,” David muttered as he pencilled the first entry into his journal. “Wind, sou-sou east, overcast, 54 degrees F.” Each day over the coming months on his way back to York Factory, David entered similar data into his journal. Joseph Colen, the new factor; will be impressed , thought David, when the route from Cumberland House to York Factory was completely surveyed for mapping.
Colen, however, was a man of business with little patience for meteorology or map-making. He was under pressure from the North West Company, whose traders had penetrated his territory and were siphoning off valuable HBC furs. Colen’s future and chances for promotion in the company depended on how well he was able to compete with the rival company for market share. When Thompson arrived, Colen immediately set him to work in the warehouse overseeing the grading and bundling of furs. When that work was completed, he sent him by the same route back to Cumberland House to collect more furs for the factory.
Even Turnor, when he arrived a year later, could not persuade the ambitious fur merchant to see the value of a map. With Turnor’s influence, however, David was appointed surveyor. He was at the end of his seven-year apprenticeship, and the directors in London gave instructions that he was to survey another trade route to the rich Athabasca country. But Colen knew how to sidestep orders from London. He could make sure his newest recruit wasn’t wasted on mapping Athabasca, but was used as he needed him – for fur production and the commerce of the factory.
For the next five years Thompson was sent trading into the Muskrat Country, the well-known, waterlogged, bug-ridden region between York Factory and Reindeer Lake. He took astronomical observations and fixed positions as he travelled, but routine company business, piled on by Colen, occupied most of his time. Finally, in 1796, Colen couldn’t stall London any longer, and he reluctantly gave Thompson permission to map a new route to the Athabasca. Colen could still influence the outcome, however, and he knew that without good men and sufficient supplies the expedition would likely fail, thus putting an end to London’s incessant demands. Colen also had Thompson’s most recent editions of the Nautical Almanac from London. For the last two years he had somehow forgotten to send them forward. What Colen didn’t count on, though, was the determination of the young surveyor.
On June 10, Thompson headed north on the Reindeer River. He was spared no company men and given no canoe. Undeterred, he hired two inexperienced Chipewyan youths as guides and constructed a birchbark canoe himself. The meagre ration allowed him meant his small party would have to rely on a fishnet and a musket for food as they advanced toward the treeless northern barrens. Secured in the belly of his five-metre canoe were his surveying instruments and notebook, a small tent and bedding, thirty rounds of ball ammunition for caribou, two kilograms of shot for geese and ducks, two kilograms of gunpowder, and three spare flints.
They travelled fast under the light load for the first week, but eventually the rivers lost depth and they began tracking. When the waterways shallowed further, they carried their canoe and pack for eighty kilometres over rocks and mosquito-infested marshes before finally reaching Lake Wollaston on June 23. Over the next two nights, while his guides rested, Thompson was busy with sextant and pencil completing notes for the survey.
They paddled across windswept Lake Wollaston for several days before finally descending the treacherous rapids of the Black River to Lake Athabasca. Six hours onto the lake they came to a protected shore well suited for a canoe camp. To their surprise, the site had been used before. Here, on a blazed pine tree, Thompson discovered the survey marking of his old master. It read “Philip Turnor – 1791.” Finally, after five years of frustration, David had mapped another route to the fur rich Athabasca region. Now he faced a bigger challenge: the long journey home.
Trail weariness had crept up on the men, depleting their strength imperceptibly each day, until they were exhausted. Such fatigue, unheeded, compounds even small problems. In this weakened state their judgment was impaired and their reactions were slowed. That is how it was when Thompson tried to line his canoe homeward up a stretch of rapids. The young Chipewyan guides, weary and unmindful, allowed the river’s current to shear the canoe crosscurrent. Thompson, slow with his paddle, corrected too late and was now faced with the threat of capsizing. He sprang forward and cut the bowline with his knife, but he had forgotten the falls behind him. By the time the sluggish crew noticed the line was slack, Thompson was plunging headlong nearly four metres over the cataract. He was battered brutally
