One of the least-known addresses in downtown Washington, Slate Alley, was once home to dozens of black and white residents who lived behind what is now the Warner Theatre. Their home addresses as well as glimpses of their lives have come to light in a new report based on extensive archaeological digs and research into old land records.

Those who lived in small houses in the alley, as well as the tradesmen who worked in the buildings facing the street, smoked tobacco in clay pipes, bought imported dishes, drank a lot of wine and eventually threw away more than 8,000 items to prove it.

The Kaempfer Co., which commissioned the study, is restoring the 66-year-old theater on 13th Street NW and constructing an office building behind it. To qualify for a $4 million federal grant, the company had to agree to an archaeological survey of the land where the new building will stand. Last summer, a team of eight dug a dozen three-foot-deep holes, sifting dirt through fine screens to find tidbits of former lives.

Archaeologist Janice G. Artemel, who worked on the dig, said the deep excavations required for parking garages wipe out all traces of former buildings and lives.

"This is something of a crisis for us in urban areas," she said. "Because of the underground parking, we either get it now or we never get it. It used to be that buildings were simply built atop old foundations. No more."

This week, Byrne Murphy, Kaempfer vice president of development, saw some of the liquor bottles, broken plates and bits of decorated pottery for the first time. He was shown the findings when he received the final report.

"I had expected two or three baggies with some scrapings," Murphy said as he cradled a graceful milk pitcher. "We are delighted there is so much to see. This will help today's public get involved with the life that was here even before the Warner."

Artemel said the dig was significant because it proved for the first time that D.C. alley dwellers of the mid-1800s engaged in "junking," the collecting of bottles and other throwaways in hopes of reselling them. In one of the three-foot holes dug inside an old carriage house, they found a pit filled with more than 500 bottles. Before this, historians had written of "junking" but never found any evidence of it.

Alley dwellers were usually the poorest of city residents who rented tiny houses built by landowners at the rear of their property. At one time, 3,000 of the dwellings existed in the city.

Those who lived in Slate Alley were considered part of the "hidden city" because neither their existence nor their houses were officially acknowledged by the District until about 1860. Census takers, and others, were not eager to visit the alleys, which had a reputation for being unsanitary places that bred disease as well as crime.

Slate Alley, named for a slate yard that operated in the alley in the 1850s, has disappeared into a vast excavation hole.

The findings -- bottles, dishes, toys, printer's type -- are the things ordinary people owned in the last century.

"The objects we found were used every day," Artemel said. "People discard what they don't want."

The report, which details more than 200 years of the site's history, was compiled by Engineering-Science Inc. and will become part of the archives of the Warner Theatre.

Early on, the Conoy Indians camped in what is now downtown Washington. They were followed by Richard Prinner, who received 500 acres surrounding the modern-day Warner site as a land grant in the mid-1660s. At the time, the land was part of Maryland.

By the time what is now the District was designated as the site of the future capital, David Burnes had inherited 172 acres of the original Prinner property. Known as "crusty David Burnes," he and others made a fortune when they sold their farmland to the federal government.

In 1800, three houses were present on the Warner Theatre block bounded by 12th, 13th, E and F streets NW.

By mid-century, following the installation of a sewer line and the graveling of muddy E Street, the block was crowded with tradesmen including wheelwrights, tinsmiths, blacksmiths and carpenters. The report notes that at least one of the new businessmen was black, shoemaker H.C. Hand.

Historians believe Slate Alley was occupied as early as 1853 but it did not appear in a city directory until 1871. In 1880, 37 heads of households were counted. The number had dropped to four in 1914. By that time, social reformers decided the alley residences were unfit and the federal government moved to demolish them or have them converted to carriage houses or garages.

The successive waves of immigrants -- Irish, Germans, Jews, Chinese, French, Swiss -- who came to Washington owned buildings on the block. By the 1920s, most residents had left the block as public transportation improved. In the 1950s, tall office buildings replaced many of the original structures.

Part of the cycle of demolition and rebuilding is reflected in the ornate Warner Theatre, built in 1924 on four of the old commercial lots. At the time, there were more than a dozen legitimate theaters and movie houses in downtown.

When the Warner closed for restoration in 1989, it was the last of the old downtown movie palaces. The theater, which will feature both movies and live performances, will reopen in 1992.

As to the artifacts unearthed in Slate Alley, the graceful milk pitcher now decorates Murphy's desk. He said the bottles and dishes will go on display in the theater lobby.