The day after Eliza Williams was detained for running away, she gave birth to a baby girl in a D.C. jail. Mother and child were released 28 days later to a slavemaster who paid a fee of $11.20 for their keep.

Not much else is known about Williams or her brush with the District's legal system in 1849. The jailer's journal, a six-column, oversized brown ledger, reveals only the briefest of information about the 400 slaves who were either held as runaways or left by owners for "safekeeping" between 1848 and 1862.

The tattered log, discovered by an employee of the D.C. Corrections Department in October, presents an unusual opportunity to look at Washington in the mid-1800s, when slaves were openly sold in the city and the keeping of slaves was legal.

Kathryn Smith, president of the Historical Society of Washington, called the log "extremely rare."

"Documents on the slave community in pre-Civil War Washington are almost nonexistent," she said. "I don't know of any other document like it. We have very little information on individual slaves by name."

Smith said the log gives researchers something invaluable: full names of slaves, the dates they were in Washington and the names of their owners. Because of the legal status of slaves, such information was not always officially recorded, making genealogical studies on some black American families difficult or impossible.

The log was found by Irma Clifton, property manager for the Lorton Correctional Complex, when she was sorting through stacks of journals and other memorabilia that were stored in her office. The historical items were stored in her office after a museum maintained by the Corrections Department was closed three years ago to create more dormitory space.

"They gave me four hours to clean out the room," Clifton said. "We had nowhere to put things, so they ended up in my office."

The less-fragile museum items are stored in a secure area in a nearby warehouse. Piled atop display cabinets are prisoner-made bricks dating from 1913 and the spaghetti pot and hotplate used by Joe Valachi, the mobster who described the workings of the Cosa Nostra crime organization to Congress. Valachi, who claimed to be quite familiar with mob tactics, insisted on cooking his own meals when he was in the D.C. jail in 1963.

The city's electric chair, in use from 1928 until 1957, also is part of the museum collection now in storage. The four-foot-tall, dark oak chair is crisscrossed with thick leather straps. Perched on the top of the chair are the leather helmet and cuffs worn by those condemned to electrocution.

Among the items Clifton took into her office was a book-sized, custom-made wood case with a locked glass cover.

Inside, an 1850-1855 detention journal was opened to display two pages. When Clifton noticed the entries were fading, she broke the lock and lifted the journal to close it. Underneath was the slave log. It had served as a prop for the book on display.

"I opened it to see what it was," Clifton said. "Then I got really excited and started calling people."

In the log devoted to slaves, jailers had recorded their arrival and release. The daily fee for men, women and children appears to have started out at about 20 cents and peaked at about 82 cents during the Civil War.

The hundred or so pages contain some entries with a first name only, such as Tom, Clancy or Margaret. Another identifies a slave as "Robey's Boy." In 1862, several of those held in the jail were released "by order of the secretary of state," with a notation of "no fee paid."

The last entry in the log is on a torn page dated April 16, 1862, that lists Robert Grey as a runaway. That is the same year that slavery was abolished in the District and owners were compensated for the loss of their property, Smith said.

The slaves may have been held in the jail that housed other prisoners, on the site of the present-day National Building Museum in the 400 block of F Street NW. From the same time period, Clifton has logs of Washingtonians and others who were arrested for the crimes that plague the city today: robbery, theft and murder.

A journal covering 1864 frequently lists running a "bawdy house," now called a house of prostitution, as the charge. Most of those arrested were women who, when found guilty, faced harsh penalties. Julia Dean, arrested and convicted on April 18, was fined $300 and ordered to jail until she paid.

Clifton said she is concerned about the security and long-term care of the slave journal and the bookcase full of detention journals covering the last 150 years. There also are boxes of unsorted documents, including prisoner transfer papers signed by Frederick Douglass when he was U.S. marshal in the 1870s.

Smith says such valuable documents should be protected from continual exposure to light, stored in acid-free boxes and maintained in a controlled environment.

But Clifton says there is no money available to properly store the paper records or space to display any of the artifacts formerly housed in the museum. Clifton said she feels strongly that the records should remain with the Corrections Department and not become part of a larger collection, such as the National Archives, where they would be stored and not seen.

For Clifton, a deadline is nearing. She plans to retire from the department next year after 25 years of work at Lorton.

"My goal is to have this matter resolved," she said. "Once I leave, I don't know who will care about all these books."