THEY WERE LOOK-ALIKES, the same apple glow to the cheek, the identical twinkle to the eye. They were sound-alikes, their thin, singsong voices soaring high. They were act-alikes, predictable as to principle, inscrutable as to political course. True, the father called himself a Jeffersonian Democrat; the son an Independent. Sure, the father never quite endorsed a Republican for president; the son actually did.

To Byrd-watchers, however, such differences are crumbs. One who observed Harry Byrd Jr., unbeaten at 66, announce his retirement last week after three terms in the Senate saw son Tom at his side and an invisible father whispering in the ear, the senior Byrd's exquisite timing part of the son's political farewell.

There has been a parade of Byrds across the pages of Virginia history: William II, the celebrated diarist, founder of Richmond and squire of Westover; Richard, the famed South Pole explorer; and Harry Sr., Virginia's politician preeminent. Lastly, there was "Little Harry," as Sen. Byrd Jr. was once called, by some to distinguish him from his father, by others because they could not.

Father and son shared common values: chivalrousness, integrity, conservatism and, in an egalitarian day, the splendid obsolescence of noblesse oblige. These are values to which Virginians, in headier moments, stake proprietary claim. The Byrds symbolize these values. The Byrds flatter Virginians' sense that they are elect and unique. The hereditary aristocracy that is the Byrd family gratifies old Virginia's Anglophilic craze.

In Virginia, the Byrds monopolize tradition. In the Richmond area, there is a Byrd Theater, a Byrd Airport, a Byrd Park, a Byrd Junior High School. Which Byrd? It matters not, and no one bothers to ask.

The tradition has its seamier side: public schools in Norfolk and Charlottesville shut down by the state in 1958 to avoid the slightest trickle of racial integration; schools, roads, hospitals that to this day are underfunded; an outlook on state government as upright as it was inflexible and dull. At the federal level, the Byrd organization philosophy of pay-as- you-go was a welcome antidote to deficits funded through federal printing presses. At the state level, it permitted a parsimony born of Virginia's Reconstruction poverty to endure long past the day when Virginians could afford more.

The "organization," as it was called, antedates even the late Sen. Byrd. Before Byrd Sr. it was known, after another U.S. senator, as the Martin machine. In it, Byrd's father, Richard, and uncle, Henry Flood, played prominent roles. Under Harry Byrd Sr., the organization entered its Augustan age. The county courthouse, with its statue of the intrepid Confederate infantryman, became its symbol. Southside Virginia -- the state's Black Belt and old plantation country -- became its backbone. Social and political repute in rural Virginia became much the same. Politics centered on the "courthouse crowd" -- the county clerk, commonwealth's attorney, treasurer, commissioner of the revenue and sheriff. In the Great Depression particularly, such jobs were plums, not squandered on the unfaithful.

Political preferences of courthouse officials and state legislators filtered up to the senior Byrd and the organization's high command. Once a consensus was reached and Byrd's blessing bestowed upon a candidate, loyalists were expected to close ranks and deliver majorities. No charter, no oaths, no formal understandings were required, only the message that advancement came through good apprenticeship, the idea not of reform, but of conformity.

In his book, "Southern Politics," V.O. Key Jr. termed Harry Byrd's Virginia a "political museum piece." Democracy was a medicine best administered in small doses. The poll tax assured a shrunken electorate; in critical Democratic primaries only 5 to 7 percent of Virginia's adult population ever went to the polls. From Francis Pickens Miller at midcentury to Henry Howell in the 1970s, populists have been held in profound distrust. Politics was thought to function best on stability, predictability and a healthy absence of public interest and emotion. When, in the '40s and '50s, emotions were turned on -- over labor unrest, the national Democratic platform and public school integration -- it was to rally sentiment behind the status quo, never against it.

It was in this environment that Harry Byrd Jr. cut his teeth. In the state Senate, he was among the most massive of all resisters to court-ordered integration. Byrd Sr. had made his mark in 1923 opposing state highway bonds; Byrd Jr. in 1950 designed a tax refund bill withholding money from schools when Virginia had the lowest rate of high school attendance in the nation. In 1960, the organization assailed Gov. Lindsay Almond's proposal for a state sales tax, in part to punish Almond for permitting integration. If there was to be change in Virginia, it would come in sanctioned ways. The statewide sales tax, the community college system, general obligation bonds, state constitutional revision, the advent of liquor by the drink occurred in the late 1960s under the aegis of the last of Byrd's "anointed": in Gov. Mills E. Godwin Jr.'s remarkable first term.

The '60s in Virginia politics was still a time when orthodoxy was rewarded. Gov. Albertis Harrison, an organization stalwart, appointed Byrd Jr. in 1965 to fill his ailing father's Senate seat. In the ensuing 1966 Democratic primary, Byrd Jr. barely won, while two octogenarian allies, Sen. Willis Robertson and Rep. Howard Smith, barely lost. Conventional explanations of the difference mostly had to do with age. Later that year, I met a voter convinced he had helped reelect Harry Sr. Quickly I checked any impulse to correct. Which Byrd mattered not. The ballot cast would in all events have been the same.

Once in office, Byrd Jr. nurtured the strengths of his name. His reelection victories in 1970 and 1976 paid skillful homage to the past. In 1970, four Virginia cities faced imminent court-ordered busing. Byrd Jr. stood squarely for tradition: the neighborhood school. In 1976, it was Byrd against Elmo Zumwalt, the senator with the cardinal -- the state bird -- as his campaign symbol against the admiral with sailors in bellbottoms and long hair.

During Byrd Jr.'s tenure in the Senate, Virginia politics underwent a sea change. Campaigns graduated from courthouse word- of-mouth to media star wars. Conservative principles, once the trust of the Byrd organization, became the property of the Virginia Republican Party. The electorate became larger, less rural and racially more diverse. Northern Virginia and Tidewater, which front the "outside" influences of Washington and the sea, gained proportionately in population over Richmond, Danville and Lynchburg, cities of the heartland. "Old Virginny," said one writer, had become "the New Dominion."

Yet the bearer of old verities survived. Amid the currents of change, Virginians somehow took Proustian comfort in voting for a Byrd: a state's remembrance of times past. Byrd Jr. survived, however, largely as a symbol, his impact limited to the votes he cast and the office he held. Byrd Sr., as governor in the late 1920s, had a lasting impact on Virginia government; Byrd Jr. never did. Byrd Sr., in a Senate of Southern patriarchs, was a force for presidents to reckon with; Byrd Jr. seldom was. Byrd Sr. loved his Virginia political organization like one of his own sons; Byrd Jr. wasn't interested. The son in some respects was a loner, the Senate's sole Independent, an affably private man who brought few into his confidence and kept even his old State Senate deskmate, Godwin, guessing his reelection intentions until the eleventh hour.

His judgments, though solitary, proved stunningly keen. The decision to turn Independent in 1970 caught state Reppublicans off guard and robbed Democrats of the chance to ambush him in their primary. The decision to endorse Ronald Reagan in mid-October 1980 was deftly timed and executed. If his Independent status lost him leverage in the Senate, it gave his word in Virginia added weight. No end of urgings -- state and national -- were brought on Byrd Jr. to endorse the Republican candidate for governor in 1981, J. Marshall Coleman. State Republicans talked of easing his road to reelection. The White House wished to couple a Coleman endorsement with a move to the Republican Party. Byrd resisted, hunkered down in one of his father's oldest habits -- golden silence -- and spared himself the embarrassment of a late Coleman endorsement followed by a shattering Coleman defeat.

Stubborn. That's how opponents privately describe the Byrds. Byrd Jr. was "stubborn" to insist on 10 white males -- "merit selections" -- for district judgeships in Virginia during the Carter administration. Byrd Sr. was "stubborn" in opposition to the Kennedy tax cut. Both Byrds were "stubborn" Johnny one-notes, stuck on balanced budgets. But it was this stubbornness that in the end exempted Byrds from perceptions of expediency, that kept a Virginia Senate seat in family hands for half a century.

No Harry Byrd in the Senate. It will take some getting used to. Change has long been upon us. Now continuity has disappeared. Some Virginians reacted to his announcement incredulously. Did he mean it? Yes, of course. Byrds have meant what they said. Byrd Jr. adored the Senate. But he retires with something few men do -- a reborn sense of relevance. The Reagan budget cuts, at least, show the word has been received.

What of the Byrd legacy in the latest Byrd's hands? It was not revised, but it was preserved. It was not magnified or expanded, but neither was it tarnished. In a family where experimentation is a form of heresy, the son has done his duty. Virginians, of all people, may understand and approve.By J. Harvie Wilkinson III; J. Harvie Wilkinson III is the author of "Harry Byrd and the Changing Face of Virginia Politics." A former editor of the Norfolk Virginian-Pilot, he is professor of law at the University of Virginia.