More valuable than artifacts in archaeologists' understanding of the Montana's demise is a detailed public record of the wreck.
"We have historical and 20th-century photos of the vessel basically degrading. We can see how it has fallen apart, and through photos we were literally able to watch this shipwreck become an archaeological site," said Corbin.
"When we can compare a full visual record with the archaeological information that we find," he added, "that yields a very complete picture of what happened on the site."
"Cutting-Edge" Ship Technology
Although various treasures were removed from the site, the wrecked ship is telling scientists much about the construction of river steamboatssecrets that nearly died when the riverboat era ended.
Any records compiled by the Montana's builder, the Coulson Company, have been lost through the years. The situation is true of most steamboat companies, which are long defunct.
Yet much about the steamship's design and origins was never recorded to begin with. "In the shipyards where they built steamboats, much like the famous four-mast clippers, the knowledge was passed down from masters to apprentices," Corbin said. "They knew how to do it, so there weren't drawings, and typically not many written records. There are a few surviving plans, but for the most part we don't have them."
Therefore, the wrecked Montana has excited scientists because it shows the technological advances in shipbuilding at that time, including those that helped pilots navigate river hazards.
The Missouri and many other rivers were shallow, which demanded design innovations and extremely skillful navigation. Any vessels that plied these rivers had to be designed to move in shallow water and be nimble enough to free themselves from sandbars and other hazards.
The exploration team had ideas about how the Montana may have been designed to meet this challenge. But the results of their study were surprising.
"When we started looking at this we were picturing a floating box with a paddle wheel," said Rodgers. "We had no idea it had such beautiful lines."
The riverbed mud showed that the ship did not have a flat, barge-like bottom, as expected, but was in the shape of a curving arch, called a "skeg." This shape did not become common in ship-building until the age of metal hulls, decades after the Montana sank.
The researchers speculated that the unusual skeg shape of the wooden vessel may have been used to help the great ship navigate thousands of miles of unpredictable river waters.
"It's tremendous to see how you could build something this large that drew so little water that it could make it all the way up these rivers," said Rodgers. "It's astounding. The technology was cutting edge for the time."
He estimated that even with a full load of as much as 600 tons, the enormous ship drew as little as three feet of water.
Last Great Steamboats
The Montana and two enormous sister ships, the Dakota and the Wyoming, navigated the river during the last glorious days of riverboat travel.
The trio was built in 1879 by the Coulson Company in partnership with other leading steamboat companies of the day. The competitors banded together to battle the new force that would eventually end the era of riverboats: the railroad.
To undercut railroad freight prices, the three ships were enormous100 feet (30 meters) longer than conventional paddle wheelersso they could carry more cargo. For a few years they were successful, traveling as far as Fort Benton, Montana, an inner port 3,000 miles (4,827 kilometers) from open water.
The steamboat era was one of booming commerce, with many ships plying the major rivers of the West.
Researchers say the remains of many of these ships lay awaiting exploration, ready to yield more insight into a romantic era. Corbin believes there may be more shipwrecks in Missouri than in any other state. Some 700 to 800 wrecks were documented on the Mississippi River alone.
"We're going to have to find them," Rodgers said.
The lives of these ships didn't last longthe average lifespan was only about four years"so they littered the rivers out West," he noted.
"But nobody has gone out systematically to find these things and investigate them," he said. "There are lots of mysteries still to solve, and we need to get hold of some intact ships to fill in our knowledge. But the Montana was a tremendous beginning."
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