He single-handedly mapped first more of North America than any other person in history yet most Canadian school children don’t even know that he existed.

Andy Korsos, the official David Thompson Bicentennial Cartographer, wants this to change. Korsos gave a presentation at the Jasper-Yellowhead Museum and Archives this Saturday, August 14 on the man who has been described as the greatest land geographer who ever lived: David Thompson.

Much of Korsos talk focused on Thompson’s mapping of the Fraser River between 1807 and 1812 and his search for a passageway to the Pacific Ocean and the Asian markets beyond (“It’s funny, 200 years later and things haven’t changed; we’re still trying to find a route to China,” said Korsos). Korsos brought a copy of a David Thompson great map of these travels that he recently obtained from the British Museum. 

The map details rivers such as the Fraser, Peace, Athabasca, Columbia and a mass of other rivers on the west coast of Western Canada. At its time, it was the most detailed map ever created for Western Canada. It might have even been the most detailed map produced anywhere in the entire world. Korsos spoke with great enthusiasm about the copy of the map he had recently acquired, which he said was one of the best representations of Thompson’s original maps that he’d ever seen.

“When I first got it, I just put it on the wall and stared at it. I just couldn’t believe the condition it was in,” said Korsos.

The main theme of Korsos’s presentation was just how amazing a cartographer and scientist Thompson was for his time. Using a compass, a watch, and a sextant (along with his brain and senses), Thompson was able to map over 3.9 million square kilometers of North America and massive sections of Rocky Mountain river systems. Korsos pointed out that even handling a metal object like Thompson’s sextant in the cold Canadian winters while outside would have been a hardship. 

Then there’s the actual work to properly draw up the map. The cartographic calculations to produce the map were done by Thompson by candlelight at the end of a dawn until dusk day of dog sledding, hiking, portaging or rowing. Taking measurements that he gathered during the day, he used his brain and the stars to make complicated calculations that we use calculators for today.

Korsos pointed out that in a region like the Peace River and its portage to the Fraser River, 98 per cent of the small tributaries and streams have been mapped out by Thompson.

“There’s just so much detail that you’re left asking ‘Why?’” said Korsos. “We’re still trying to figure it out.”

Korsos was careful to point out that you can’t travel to the longitude and latitude positions of Thompson and actually arrive at the point that he intended. That’s because Thompson was using a different grid system than we use today. If you move Thompson’s longitudes and latitudes over into the present day system however, they line up with a high degree of accuracy.

“There’s absolute and relative accuracy and Thompson may have been off absolutely, but relatively, he was very, very accurate,” said Korsos.

Thompson had to overcome significant other hurdles in his map making. In a section along the Fraser River that he mapped with explorers Simon Fraser and John Stuart, Thompson draws the Fraser River jumping significantly to the east. The reason Krosos believes: magnetic declination and extreme jumps in the readings of magnetic and true north, a “nuisance to navigators and surveyors for centuries, including today,” said Korsos.

While the explorers would have understood the general idea behind magnetic declination, they didn’t have a map of where it would occur. “It surely would have lead to some very interesting conversations like ‘What the hell is going on?’” said Korsos.

The fact that some of Thompson’s most major mistakes can be attributed to something as confusing as magnetic declination shows that he was really a great explorer, Korsos said. It took the shifting of the magnetic north pole to throw Thompson off of his map making game.

The British Museum map Korsos showed off is full of interesting tid-bits, interesting asides and historical mysteries.

One hundred kilometres up the Columbia River’s entry into todays’ Washington State, there is a written marker signifying that in 1792, ‘to this place, the white man came from the sea.’ Korsos said that no one knows who these white men are. It wasn’t until 1826 when the Columbia River was fully traversed from west to east.

“We just don’t know,” said Korsos. He added that he’s got historians at the University of Winnipeg rolling around trying to figure out what Thompson was referring to.

Korsos added that in the British Museum archives, there are likely maps that Thompson had a hand in creating that haven’t even been seen since they were originally sealed, their 200-year-old seals just waiting to be cracked.

“There are hundreds of thousands of maps they haven’t even looked at yet,” said Korsos.

At the end of Korsos’ talk, one man asked him bluntly what is the point of gathering all of this information about David Thompson’s map making skills.

“It’s a confirmation of just how good this man was as a scientist,” said Korsos. It’s amazing to think that a man could travel through the Athabasca Pass during the dead of winter on equipment that we now call antiquated and that this man was so dedicated to science that he was willing to stop in the waist-deep snow and dissect a moose’s brain.

“This guy was brilliant,” said Korsos.

Beyond this though, Korsos articulated a vision of David Thompson as a source of Canadian national identity. Korsos said many people define Canada through multiculturalism. He said that’s fine, but he sees a different vision.

“Perseverance: the trademark of the North-West Trading company,” he said. “It’s who we are.”