After 1450, the people who lived in an area that stretched from St. Louis to the Arkansas border and from Nashville to the Ozarks all but disappeared.

Archaeologists don't know what happened to the Mississippian culture, but most of what they do know about it is gleaned from artifacts like those found in Southeast Missouri State University's Beckwith Collection.

Stephen Williams, a professor of American archaeology, emeritus, at Harvard University, spent part of Wednesday examining the Mississippian collection he calls "one of the best."

Williams came to Southeast at the invitation of Dr. Carol Morrow, an archaeology professor at Southeast. While here he also taught a class in historic preservation.

A frequent visitor to Southeast Missouri during his career, Williams today is showing Southeast president Dr. Dale Nitzschke the Mississippi County sites that yielded the Beckwith Collection.

From 1958 to 1993, Williams headed the Peabody Museum's Lower Mississippi Survey, its longest-running research project. But while still a graduate student at the University of Michigan in 1950, he was sent to Southeast Missouri to look for the clay balls Beckwith called "sling stones."

Not everyone valued the mounds that these artifacts came from. One farmer Williams talked to at the time claimed that a conical mound was in his way. A few days later he tore it down with a dragline.

Williams took photographs of the collection back then and on this visit brought copies so museum director Dr. Jenny Strayer could make comparisons.

Most of the Beckwith Collection is always in storage, partly due to the University Museum's limited space. But it is viewed as an under-used resource.

"We are looking for ways to integrate this collection into the curriculum," Strayer said.

Thomas Beckwith excavated the artifacts between 1870 and 1900. "There were Indian mounds on all the farms there. He couldn't not be interested," Williams said.

Beckwith also allowed the Smithsonian Institution to dig on his property on Pinehook Ridge.

Yale and Harvard's Peabody Museums have extensive collections of artifacts from Southeast Missouri. Williams directed Harvard's Peabody Museum for a decade.

Williams' "Vacant Quarter Hypothesis" is one of many mysteries presented by the Mississippians. Examining a female effigy in the Beckwith Collection storage room, he says archaeologists don't know why many of the effigies have hunched backs.

The Mississippians are the opposite of the Mayans, Williams says. Little is known about the elite.

"These were common folk. They lived in villages and small towns surrounded by walls. There was a definite class structure."

No burial tombs of the ruling class have been located. "And they probably will not be found," Williams said.