J. Carter Brown, director of the National Gallery of Art, testified in court yesterday that four high-rise buildings planned in Rosslyn would be "a visual intrusion akin to an act of urban vandalism."

Only "if a building were wrapped in neon and allowed to blink" would it be more of an intrusion, declared Brown, who also is chairman of the federal Fine Arts Commission.

Brown's testimony came on the opening day of the trial in U.S. District Court in Alexandria of a suit in which the federal government argues that the buildings, two of which would be 29 stories tall, would ruin the sky-line surrounding the nation's capital and therefore constitute a public nuisance.

A different view is expected to be explored in court today as the defense presents its case. Court papers filed by the Arlington County Board, which granted zoning for the buildings and is one of the defendants in the suit, argue that the structures will "improve the quality of civilization."

Yesterday's testimony by Brown and other government witnesses was punctuated by frequent exhortations from Judge Oren R. Lewis to "get on with the case."

As Brown was testifying about the original plan for the nation's capital, the site for which was chosen by Thomas Jefferson and Pierre L'Enfant, Lewis interjected: "I won't let you give Thomas Jefferson's opinion. You are not to argue this case."

The judge then remarked, "you show him a picture and he wants to give a dissertation on Thomas Jefferson."

In their testimony, Brown and others stressed their belief that the three office buildings and one hotel planned for Rosslyn will reverse nearly 200 years of architectural history.

Under questioning by Lewis, both Brown and National Capital Planning Commission director David Childs conceded their agencies have no legal jursidiction over buildings in Virginia but they said they feel a "moral responsibility" to protest the buildings.

In addition to the allegation of nuisance, Justice Department attorneys charge that Arlington officials violated zoning laws in approving the buildings and failed to give federal authorities adequate notice prior to their approval.

Arlington officials have denied improprieties.Testimony yesterday by Childs disclosed that the planning commission had been notified prior to the approval of one of the controversial buildings.