Goyette thinks such fears are ill-founded. "If you walk across Mass Ave you might get hit by a truck, too," he said. Jacobsen acknowledges that he can make no guarantees, but said that with careful planning the construction can be almost risk-free.

Opponents say that there is no need to take any risk at all, since the library could be built on an unlandscaped site 600 yards from the main house.

"The convenience of the scholars has come before the garden," Schenk said, "Why can't they get off their asses and take a four-minute walk once in a while?"

Goyette agreed that contiguity is the main advantage of the original site, but added that such proximity is vital both to scholarship and to the security of the rare books.

Schenk said he believes that the integrity of the garden is at stake. He said the planners are not sensitive to landscape questions because they are "indoors people."

"Some of them," he said, "honestly couldn't tell an azalea from an ivy."

Dumbarton Oaks became something of a household name in 1944 when it hosted the conference of Allied ministers which helped lay the groundwork for the formation of the United Nations.

After the war the Byzantine scholars moved in, but in 1947 they put their books aside long enough to hear Igor Stravinsky conduct the premiere of his Dumbarton Oaks Concerto