In the bowels of U.S. Bank's basement in downtown St. Paul, Kenton Spading follows guard Linda Traen into the carpeted vault lined with rows of safe deposit boxes. She reaches up to the second row from the top and unlocks a steel door. Spading delicately withdraws a large photo album containing 137 historic photos of the Mississippi River taken in the 1880s.

"They're in pretty remarkable shape, considering they bounced around on a dredge for more than 50 years," said Spading, a hydrologic engineer with the U.S. Army Corps of Engineers.

Remarkable - and valuable.

A photography expert from Sotheby's, the international auction house, flew in from New York recently and spent a day with the old photo album before appraising it at $4.5 million.

For a few Henry Peter Bosse aficionados, including a great-nephew who lives in Minneapolis, the whopping appraisal came as little surprise. But to the rest of us, the value placed on old album raises a few questions:

Who in the heck was Bosse (pronounced BOSS-ee)? Did his obscurity contribute to a string of misfortunes for his artwork, with albums vanishing and glass negatives shattered?

What's a governmental branch such as the Corps of Engineers doing with such a valuable book? And what's next for Bosse's serene, oval cyanotype images of the Mississippi cast in a moody, bluish light from an ancient photographic process?

From Prussia to St. Paul

Born in 1844 in Prussia (now Germany), Bosse came from good stock. His grandfather, Count August Neidhardt von Gneisenau, was a general who helped defeat Napoleon at Waterloo. And before that, his forebears included renowned French engravers.

He was classically trained in engineering, art and music before emigrating to North America in his 20s. He showed up in St. Paul for four years in the 1870s, working as a draftsman and mapmaker for the Corps of Engineers just as the Mississippi was morphing from a wild, rapids-laced river into a navigational stream of commerce with bridges, steamboats, locks and dams.

As he charted the river, Bosse dragged along his large 11-by-14 camera, composing shots of bridges and scenery, often keeping his lens open so long -- to capture adequate light -- that the river's movements were blurred.

"He set things up like a painting and captured the first major transformation from the natural to the commercial river, with railroad and wagon bridges and the growing frontier villages," said John Anfinson, a river historian with the National Park Service.

The asparagus did him in

Bosse died in 1903 at age 58 after eating asparagus that his wife had served from a glass jar. A mistake in the canning process led to food poisoning, and he died in a hospital after suffering a heart attack.

"He was a large fellow and he might have been predisposed to congestive heart failure, but the asparagus did him in," said Mark Neuzil, a University of St. Thomas professor who wrote a coffee-table book 10 years ago for the University of Minnesota Press called "Views on the Mississippi, the Photographs of Henry Peter Bosse."

After his death, Bosse was largely forgotten.

But he left photo albums behind. The Mayo Clinic Foundation has one, as does a steamboat museum in Dubuque, Iowa. When an antique dealer on the East Coast sold one for $66,000 in 1990, the world rediscovered the Prussian draftsman and his keen eye.

Anfinson, then working for the Corps of Engineers, did some research and learned that one of the Bosse albums had been given to the dredge William A. Thompson at its christening in 1937. Thompson, a Corps engineer who died in 1925, had worked alongside Bosse. Although no one's sure, their widows might have been behind the album-to-dredge donation.

Anfinson called the dredge, which was working on the river near St. Louis, and asked: "Do we have a book of blue photographs?"

Yep. They'd been sitting on the captain's desk from 1937 to 1989. With no stains from coffee cups, odds are no one pulled it out much. Once the dredge returned upriver to St. Paul, Anfinson snatched up the book and put it in the vault. It was appraised then at $1 million and has quadrupled in value in the 20 years since.

Spading said the Corps decided in recent years that a vault wasn't the best place for it, so they're negotiating to lend it to the Minnesota Historical Society to conserve it in climate-controlled archives. Perhaps it will be put on display. The Historical Society requires an appraisal before taking items into its collection, so that prompted the Sotheby's visit a few months ago.

As for the other Bosse albums, the Rock Island, Ill., office of the Corps, where Bosse worked after leaving St. Paul, had a few albums and the original glass-plate negatives. One of those albums is missing, Spading said, and might have been checked out from the Corps library before its value soared.

"If so, whoever finds it should know that we still own it," he said.

Meanwhile, all but a half-dozen of the glass-plate negatives were broken when movers dropped them while descending stairs a few years ago during a Rock Island office reorganization.

Retracing footsteps

Chris Faust, a renowned panoramic photographer whose work hangs in the original Dunn Brothers coffee shop in St. Paul, had never heard of Bosse until 1990. The Corps asked him to make copies of the photographs, and as digital technology improved, he's returned to sharpen his copies with computer help. In the process, he's become a Bosse convert intent on keeping his legacy rolling.

Faust is launching a project to re-photograph about 60 of the images, trekking in Bosse's footsteps -- or as close as he can get. Many of the original images were made at places such as Mechanic's Rock, which has been underwater since the locks and dams came in.

"There have been some radical changes to the riverbanks," Faust said. "But some of the changes aren't detrimental to our eye and show how nature and humans have worked around each other, negotiating this landscape."

He's hoping to raise money from national and state grants and other sources to rent a boat this spring.

"Sometimes, Bosse was standing on sandbars that no longer exist," Faust said. "I have a retired barge captain who really knows the river and is ready to help."

He plans to publish a book of Bosse's images side-by-side with his present-day shots and hopes for a major museum exhibit in coming years.

Back in the anteroom adjacent to the St. Paul bank vault, Spading turned pages in the old album until reaching his favorite: "Construction of a Rock and Brush Wingdam, Low Water, 1891." The image shows men on a barge placing boulders on beds of willows, sinking them to form the first dams on the Upper Mississippi.

"These images make my jaw drop," he said. "They are not just photographs -- they are works of art."

Curt Brown • 612-673-4767