Vice President Bush, Chief Justice Warren Burger and Smithsonian Secretary S. Dillon Ripley broke ground in a ceremony last night for the Smithsonian's $75 million Center for African, Near Eastern and Asian Cultures.

When it opens in early 1986, the center will exhibit art and artifacts from nearly 100 nations from "the Atlantic shores of Africa to the Pacific shores of Asia," Bush said in his speech.

The vice president praised the scope of existing Smithsonian museums, but added that "there really was a large gap . . . the cultures of these nations have been insufficiently recognized."

Ripley, who is retiring next year, said at a reception after the ceremony, "This is really something I've been dreaming about for years. I just hope I can see it done with the style and taste and flair that it needs. It's got to be done well. If it isn't done well, I'll eat my hat."

Burger said in his speech that John Quincy Adams, after he had been president and was back in Congress, had been floor manager for the bill accepting the bequest of British scientist James Smithson that established the Smithsonian Institution in 1847. Now, Burger quipped, Washington has become "a small sleepy southern town on the outskirts of the Smithsonian campus."

The 368,000-square-foot underground center will house the Smithsonian's National Museum of African Art, now in several town houses on Capitol Hill, and the new Arthur M. Sackler Gallery, which will include 1,000 masterpieces of Mideastern and Asian art valued at $50 million and donated by Sackler, a New York research psychiatrist, medical publisher and arts patron.

Last night, Sackler, smiling and jovial in a dark business suit and bow tie, handed Bush a $2 million personal check--the first half of his $4 million contribution to the project. Bush accepted as vice chancellor of the Smithsonian. Burger is chancellor.

"It's a very privileged moment and one that I think bespeaks the greatness of a nation based upon a philosophy which I believe represents the greatest hope for all of mankind in the years ahead," Sackler said later at the reception.

The center will be entered through two ground-level pavilions set in a four-acre, 19th century-style garden, but the bulk of the exhibition and working space will be on three underground levels. There also will be an underground center for international scholarly conferences, space for major traveling exhibitions, classrooms and offices.

The site is just south of the Smithsonian Castle near Independence Avenue and 10th Street SW, an area known as the Quadrangle. The Smithsonian's Arts and Industries Building is just to the east, the Freer Gallery of Art just to the west.

The Sackler Gallery will be connected by an underground passage with the Freer, one of the world's great collections of Oriental art. Freer director Thomas Lawton also will be in charge of the Sackler Gallery.

The brief groundbreaking ceremony was held outside under a small tent because of the threat of rain, with most guests watching the ceremony on closed-circuit TV from inside the Arts and Industries Building. A reception there later featured performances by artists from the cultures whose arts will be studied and displayed in the new center.

Guests included Sackler and his wife, Jill; Sylvia Williams, director of the National Museum of African Art; former District mayor Walter Washington; Warren Robbins, who founded the African museum, and a number of ambassadors from countries whose art will be featured in the new center, including Ashraf A. Ghorbal of Egypt and A. Hasnan Habib of Indonesia.

Williams said she and her staff already are making preliminary plans for their first "major loan exhibition," which she hopes will include works borrowed from the federal museum system in Nigeria. She said the plans are "all contingent" and that Nigerian officials have not yet been asked. The Nigerian ambassador, Chief Abudu Yesufu Eke, was invited to last night's ceremony but was unable to attend.

Taxpayers are footing half of the $75 million bill for the new center. Smithsonian officials said almost $35 million of the remainder has been raised from foreign governments and corporations, U.S. corporations, foundations, individuals, Smithsonian trust funds, earned interest and the expected sale of eight of the African museum's nine town houses.

In addition to Sackler's gift, the Pew Memorial Trust, a private charity in Philadelphia, donated $1 million, and the garden is being designed and installed with $3 million from New York philanthropist Enid A. Haupt, in whose honor it will be named.

In the brief groundbreaking ceremony, as Bush, Burger and Ripley stood poised with their shovels, the vice president said, "What's this electronic thing?"

"This will hear whatever you're saying," Ripley replied.

"Then, gentlemen," said Bush, "let's begin the Quadrangle." With that, they dug their shovels into the earth.