Washington area Jews yesterday filled to capacity the Jewish Community Center in Rockville to celebrate the Jewish festival of Purim, at the same time paying tribute to a Jewish minority credited by a speaker with making possible Christopher Columbus' voyages.

The record crowds, which at times blocked traffic briefly on Montrose Road, were there for the Center's first Sephardi festival.

World Jewry is divided into two ethnic groups: Ashkenazi Jews, who have their roots in northern or eastern Europe, and Sephardi Jews, who were scattered around the ruin of the Mediteranean and into Arab lands after they were driven from Spain and Portugal by perseuction.

Sephardi Jews account for a very small portion of American Jews. In Washington, they are an estimated 2,000 out of about 125,000 Jews in the area.

"We are just being discovered," explained the chief speaker of the day, Dr. Solomon Gaon, grand rabbi of the Sephardi communities of Great Britain and who is the present occupant of the chair of Sephardic studies at Yeshiva University in New York City.

In 15th century Spain, the rabbi said, Sephardi Jews made the voyage of Columbus possible" by helping with the financing, while other Sephardi scholars in Spain helped by providing crude maps for the voyager.

"Definitely it was Jewish initiative which brought about the discovery of America," he asserted.

Dr. Gaon devoted the bulk of his formal address to an emphasis on Sephadi devotion to the cause of Zionism.

"There are people who say that the Sephardim have not taken part in the Zionist movement and the difficulties which some Sephardim find themselves is in Israel today" is because they lack sufficient zeal for Zionism, he said.

In the world Jewish population, only one Jew in 15 is Sephardi. But about 65 per cent of Israel's Jews are Sephardic, Rabbi Gaon said, as the result of mass migration of Jews from Yemen, Morocco and other Arab countries that began expelling Jews when the state of Israel was created.

The vast majority of these Jews are poor, uneducated and lacking in the skills prized by a modern technological nation such as Israel.

Rabbi Gaon does not believe that the Israeli government discriminates against these Jews, as some have claimed. "It is too much to say that it is conscious discrimination," he said, in answer to a reporter's question in an interview following his address. "Many of them (Sephardi in Israel) are very poor and they have no higher education. Mistakes are being made (by Israel in dealing with the Sephardi) but I don't think they are made deliberately."

He said the World Sephardi Federation is very concerned about the situation in Israel. "We are trying to press the Iaraeli government and Jewish agencies to give these people opportunities, education. But that takes money," he said.

Rabbi Gaon said that Israel's Sephardi Jews, because of their familarity with Arab countries, can make a "valuable political contribution in the Middle East. They know the Arabs very well. I believe they will help bring about closer relations between the Arabs and Israel," he said.

In addition to the Rabbi's lecture, visitors to the Center yesterday examined Sephardi art and artifacts, ate Middle Eastern foods, and watched traditional dances.

The Sephardi festival was mixed with the Center's annual celebration of Purim, a light-hearted Jewish holiday celebraing the triumph of the Biblical queen Esther over an ancient Persian functionary, Haman, who ploted against her people.

On Saturday, synagogues in the area marked a more somber link to the Sephardi festival in observing the Sabbath of Concern for Jews in Arab lands.