PARK CITY — Grace Horman could not contain her excitement over what she had previously thought was a small piece of wood.
“Oh my god, I found something!” she shouted.
The 23-year-old Montana State University Billings student, wearing a fake coon-skin cap pulled down over long blonde hair, was overjoyed, yet also skeptical.
“You’re not messing with me, are you Rust?” she queried.
“No, this is bone,” said Tom Rust, assistant professor of history at MSUB, as he examined and cleaned the find. “I don’t see any marks on it, but it’s definitely bone.”
“Oh ho ho, I actually found something!” Horman squealed. “This is better than a piece of coal.”
Corps of Discovery
Horman, Rust and three others were digging in the dirt on Friday on a large Yellowstone River island, a place being investigated as the possible site of explorer Capt. William Clark’s July 1806 canoe camp.
Between July 19 and the 24 of that year, the group of 13 men cut down two cottonwood trees to build canoes 28 feet long, 16 to 18 inches deep and 16 to 24 inches wide. The trees were lashed together for stability.
The men were a portion of the 33 members of the Corps of Discovery, led by Clark and Capt. Meriwether Lewis, who had set out in 1804 from St. Louis to travel up the Missouri River and across the Rocky Mountains in search of a water passage to the Pacific Ocean. Although the group reached the ocean, they found the Rocky Mountains blocked an easy water route. Their carefully chronicled explorations, however, led to greater interest in and the eventual settlement of the West.
On their return from the ocean, the expedition split into three parties with Clark’s group riding horses down the Yellowstone River. At the canoe camp, though, Indians stole half of the group’s 50 horses.
Here, again, the group divided with three taking the remaining horses downstream while Clark and the others would canoe.
Looking for the X
Finding the campsite is important because Lewis and Clark left behind little evidence of their spectacular overland journey.
Rust began research on the island in 2011 after Billings historian and cartographer Ralph Saunders presented him with convincing evidence that — based on Clark’s original maps and diary — he had located the canoe campsite.
“I’m always skeptical, but I’m always up for a field trip, too,” Rust said.
Saunders’ work could have been dismissed had he not been so thorough in his research, even finding out what magnetic north was back in 1806. After all, eight other purported sites had been suggested as Clark’s canoe camp along a 12-mile stretch of the Yellowstone River between today’s towns of Columbus and Park City.
“Anybody with a color crayon can put an X on the map,” Saunders joked.
But his study of the original maps, historical surveys and aerial photography made him sure that his calculations had found the site — a piece of cottonwood-clad river bottom land that had once been attached to the mainland.
“It’s a miracle and kind of a blessing we were able to find this,” Saunders said, because in the intervening 200-plus years, the Yellowstone River had moved considerably. Luckily, when the river moved — jumping to an entirely different channel to the north in the early 1900s and then back again — the island seems to have been largely spared from damaging floodwaters that could have washed away any evidence of the expedition.
“Fortunately with that jump, it saved us,” Saunders said. “Otherwise the river would have taken this out long ago.”
“It’s about as miraculous as you can get,” Rust added.
Sifting for clues
So in 2011, Rust investigated the island with a magnetometer and soil resistance meter to assess soil disturbances and compaction. The hope was that the surveying could reveal old campfire sites, a latrine, butchering area and even pathways packed down as the men moved around the campsite.
“We had several metal detector hits as well, so that was terribly exciting,” Rust said.
With all of this data in hand, it became clear to Rust that certain areas looked promising for places to dig test pits and sift through the soil in search of more concrete evidence.
But 2011 was known for some of the highest flows of the Yellowstone River ever recorded. One day while working on the site in May, 6 inches of rain fell on volunteers. Despite the difficult conditions, the group’s efforts were rewarded.
“Kapow! A Boy Scout pulls up a little round thing that he thinks is a rock,” Rust said, standing over a once-turned portion of grass. “But it’s nearly perfectly spherical and made out of lead.”
Near to where the lead ball was found, at sites where the metal detector had beeped, excavations turned up nothing. Puzzled, Rust decided to use a mercury vapor analyzer to scan the same soil. The analyzer picked up a parts-per-million range of mercury that matched what archaeologists had found at Travelers’ Rest, a confirmed Lewis and Clark campsite near Lolo.
The mercury was found in latrine pits because the explorers used a medicine laced with the harmful chemical.
Although such evidence is good, Rust still hedges his statement with all sorts of qualifiers.
“In all likelihood, it is very indicative of perhaps, maybe, possibly being a latrine feature,” he said.
He also speculated that the lead ball could have fallen from one of the explorer’s cartridge cases when they laid it on the ground to use the latrine.
“I think it’s a plausible explanation,” he said.
Initially, Rust was skeptical of the lead ball because of its size — a .375 caliber. That doesn’t match any of the muskets Lewis and Clark were known to have, but they also carried private firearms and there is no known list of what they took along.
Rust also found out that during the Revolutionary War, the .375 caliber was commonly used in what’s known as a buck and ball load — a larger .69 caliber ball combined with three to six smaller buckshot pellets was used to increase the chances of hitting the target.
“So we’ve been feeling very comfortable that it could be buckshot,” Rust said.
He’s even experimented with using a 1795 musket loaded with buck and ball and found, “preliminarily,” that the .375 is “very effective.”
Also convincing is the fact that an isotope analysis of the lead musket ball matches an artifact from Travelers’ Rest. And both can be traced back to a mine in Kentucky.
“You’ve got an awful lot of coincidences,” Rust said. “You get three or four and it’s a lot harder to convince me it is a coincidence.”
The evidence collected so far is convincing enough that Rust said the National Park Service is “very excited” by what’s been found and has pitched in some funding.
Rust and his volunteers have also found some flattened lead next to what looks like a fire pit. The fire’s charcoal was tested and came back with a date of between 1650 and 1820 — a range that Rust called acceptable.
The lead didn’t test the same as the musket ball, but there was also a belt buckle discovered in the same area — all of this at the same depth of about 25 centimeters. Two weeks ago a bone was uncovered at the same depth and on Friday, two more were found.
According to Clark’s journals, while at the canoe camp the men killed at least 19 animals, including elk, deer, antelope, bears and buffalo. Rust was hoping that he could find a butchering site which, by the military dictates that Clark followed when setting up camp, would have been about 50 paces from the fire.
As Luke Renfree, a 21-year-old Dillon history major at MSUB, shook dirt from a shovel hole through a sifter he hoped to “hoist something cool out of the ground.”
“This is my first time out here,” he said. “It’s kind of a class requirement.”
For MSUB student Hannah Gibson, a senior history major, it was her third time visiting the dig site. Her most exciting find was rust marks in the dirt, although no artifact was found below the marks.
“This is actually what I want to do after I graduate,” she said. “It’s better than sitting in class. I guess I’m more of a hands-on historian. I like to learn about a place and see it.”
Next to Horman’s excitement at finding a bone, Saunders may have been the most tickled of the group.
“It’s all kinds of fun,” he said.
To find physical evidence at the place he determined to be Clark’s canoe camp 208 years ago is icing on the cake.
“In my mind, I’ve been comfortable with the site for some time, even before we found the lead,” Saunders said.
What’s even more amazing to him is that in all of that time, the often voracious and destructive Yellowstone River has left what’s believed to be the campsite relatively intact.
Of course, everything is open to interpretation, Saunders said. Yet in his mind Clark’s canoe camp has been found.
“It’s just amazing to me how it’s come together like it has,” he said.