The worst disaster of Robert Thompson's life involved a bus and a bottle of wine, but it wasn't the kind of collision you might imagine.

Thompson, a communications lawyer with Pepper and Corazzini, had visited the exclusive Berry Brothers wine merchants on London's fash- ionable St. James Street --

"plush armchairs, fresh-cut flowers, a very civilized system for buying wine." He purchased a 1970 Kirwan and a 1966 Canon -- two highly rated French Bordeaux worth about $240 in today's market. Then, wine sack firmly in hand, he boarded one of the city's red double-decker buses.

"I guess I put the sack down with extra heavy force, and . . . the bottles shattered."

That 1984 loss notwithstanding, Thompson has approximately 3,000 bottles in his private collection, tucked in a temperature-controlled cellar beneath his Northern Virginia home. One of the oldest is a 1919 Chateau Lafite-Rothschild (about $800, wine merchants say), although he rates a 1961 Margaux (about $300) and a 1945 Mouton-Rothschild ("invaluable") among the finest vintages he's ever tasted.

Thompson says he sticks to mineral water during his work week, but admits that "I drink more wine than my doctor would like on the weekends. When I do drink fine wine, I like a mature, complex wine -- by definition that's a red," he says, voicing a prejudice.

We suppose he's entitled. For several years he even wrote a wine column, for which he once researched the White House wine cellar.

"I used to really enjoy the California Beaulieu Vineyards. But when I found that it's one of Ronald Reagan's favorites, it caused me to ponder my judgment," he says, voicing another.