Samuel "Doc" Eisenberg, 98, a Russian immigrant who founded Plain Old Pearson's Wine & Liquor in Washington's Glover Park and who built it into one of the largest volume stores in the area, died of pneumonia Oct. 30 at Sibley Memorial Hospital. He was a resident of Chevy Chase.

Mr. Eisenberg founded the store about 71 years ago, just as Prohibition ended, and became a wildly successful merchant who offered discount prices, innovative merchandising and humorous, opinionated newspaper advertisements.

He did whatever would help sell beer, wine and spirits, including special appearances by a billy goat and by the Budweiser Clydesdales. He photographed 10 "mystery men" in Lone Ranger-style masks, whose mission was to sneak looks at competitors' prices all over town. A chalkboard "stock exchange" updated those prices three times a day, his ads screamed. Mr. Eisenberg would advertise almost anything: the conveyor belts that moved the store's huge inventory, the floors worn down by the tramping of "millions" of customers and the store's room-size beer cooler. Steve Silver, the son-in-law who joined the business in 1976, said that the ideas all came from Mr. Eisenberg and that the ads reflected his personality.

"He was a very creative guy," Silver said. "He was constantly thinking; his brain was always working, and every conversation he had led to an idea on how to improve the business."

In 1958, Plain Old Pearson's ran a sale to apologize for any offense given to any customer by any employee for any reason in the previous 25 years. There was a "business is lousy" sale and a St. Patrick's Day sale on Irish whiskey, with an ad written entirely in Gaelic. On the 15th anniversary of the business, Mr. Eisenberg ran a six-part series of ads to tell "the dramatic story of the rise from a $20-a-day business in the tiny corner of a drugstore to . . . $2,000,000 a year! Drama! Action! Humor! Thrills!"

Born in the Ukrainian town of Rovno in 1906, Mr. Eisenberg came to Washington with his family in 1918. As a teenager, he sold newspapers on the street for 2 cents, a penny less than the other newsboys, who promptly beat him up.

He graduated from Eastern High School and from George Washington University as a pharmacist. In 1933, he married and bought Pearson's Pharmacy at 2448 Wisconsin Ave. According to the Prohibition-era laws, customers could buy liquor if they had a prescription, so Mr. Eisenberg cleared a shelf for liquor. That prescription was soon outselling all others; luckily, Prohibition was repealed at the end of the year.

He opened "Pearson's Annex," the liquor emporium, a few doors away from the pharmacy seven months later. He owned both businesses until the 1940s, when he sold the pharmacy to concentrate on the renamed annex, which reflected his "plain old style" of sales. But he kept his pharmaceutical nickname, "Doc."

"Liquor is a good medicine, so I feel I'm still practicing pharmacy," Eisenberg told a Washington Post reporter in 1973 in his heavy Russian accent. Washington had been very good to him, he declared, because it was a "drinker's town." In 1956, his then-21-year-old son Walter joined the business, and after a year of trying to share the operation, Mr. Eisenberg put his son in charge of the wine selection. The time was right; wine prices were starting to escalate. By 1961, Plain Old Pearson's hit on a new retailing idea -- a futures market on cases of wine. Its ads featured Walter boarding a TWA jet to Europe, with a blank check in his hand, to buy up cases of the most promising vintages.

None of the store's ads attracted more attention than the April 30, 1963, full-page essay called, "Is This My City?"

With arresting white type on a black background, illustrated by a sketch of a sad George Washington, the ad deplored that in the District, "the coming of darkness signals the start of violence." Prompted by the mugging of two employees, Mr. Eisenberg asserted "if all the groups involved stopped working for the Negro community or the White community, and became concerned instead with the Washington community, we believe progress can be made."

It prompted outrage in letters-to-the-editor columns, where readers noted that liquor sales contributed to juvenile delinquency and drunken criminal sprees. After-hours liquor sales on the streets of African American neighborhoods were sponsored by liquor stores themselves, said E. Franklin Jackson, then-president of the D.C. branch of the NAACP. In 1985, Plain Old Pearson's became Pearson's Wine and Spirits. "What's all the fuss about?" Mr. Eisenberg asked in an ad. "Pearson's has changed its name before." The store still operates, now primarily as a wine shop.

He was a member of Ohev Shalom Talmud Torah Synagogue, Woodmont Country Club and Samuel Gompers-Benjamin Franklin Masonic Lodge.

His wife of 56 years, Sarah Eisenberg, died in 1989.

Survivors include three children, Walter Eisenberg of Atlanta, Nadine Needle of Potomac and Rae Silver of Chevy Chase; six grandchildren; and 10 great-grandchildren.

Eisenberg used innovative and humorous merchandising, including the 10 "mystery men" in an ad that ran in The Washington Post.

Samuel "Doc" Eisenberg founded Plain Old Pearson's.