Another small treasure of baseball lore disappeared into the rubble when Milwaukee's County Stadium was razed to make way for the new Miller Park this season. There are those of us who fondly recall the early days of the Milwaukee Brewers there three decades ago, and the misbegotten adventures of Bernie Brewer.

Bernie was the costumed mascot who sat in a perch high above a giant beer stein in centrefield. Whenever the Brewers hit a home run, which wasn't all that often, Bernie would celebrate by sliding down a steep ramp into the mug, sending up a spume of foam.

As it turned out, this lederhosen-and-Bavarian hat-clad elf had an ancillary function. When the Brewers were at bat, he maintained a vigil from his strategically located perch, armed with binoculars and a pair of oversized white gloves. He intercepted the catcher's signals to the enemy pitcher, and relayed the intelligence to Milwaukee batters.

When this bit of espionage was unearthed midway through the 1973 season, Bernie was ordered to give up the spy trade.

Whitey Herzog, who managed the Texas Rangers, a team even more hapless than the Brewers, was dumbfounded when the chicanery was exposed. "Why," he asked, "would anybody want to steal our signs?"

A certain understood ambiguity exists about gamesmanship in sport. A man who would not dream of improving the lie of his golf ball will unhesitatingly pull an opponent down by the shirt on the soccer pitch - particularly if he thinks the referee isn't looking.

At least in the absence of technological assistance, sign-stealing in baseball has historically been regarded as something of a noble tradition. When a player is traded from one team to another, he is routinely obliged to endure an intelligence debriefing. Fully anticipating this development, the old team will usually have adopted a whole new set of signals by the time they play one another.

The subject has come under increased scrutiny of late with the approaching 50th anniversary of Bobby Thomson's "Shot Heard Round the World", one of the half-dozen most celebrated events in baseball history. After trailing by 13 games in mid-August, the New York Giants had staged a torrid finish to finish dead even with the Brooklyn Dodgers that year, forcing a three-game play-off to decide the National League pennant. After the teams split the first two games, the Dodgers had a 4-2 lead in the bottom of the ninth when the Scots-born Thomson hit a three-run homer off Ralph Branca to cement what would come to be celebrated as "The Miracle at Coogan's Bluff".

Recordings of announcer Russ Hodges' breathless radio call - "The Giants win the pennant! The Giants win the pennant!" - are replayed to this day, and half a century later, at least three television networks have programmes in production to revisit the historic occasion.

It has also recently emerged that (as had long been whispered) the 1951 Giants may have significantly improved their chances by, well, cheating. A few months ago the Wall Street Journal reported that New York manager Leo Durocher had devised a system not unlike Bernie Brewer's.

AT the Giants' old home field, the Polo Grounds, the home team clubhouse was located in straightaway centrefield. Durocher had stationed a spy there, armed with a telescope, who would use an electric buzzer to relay opponents' signs to the Giants' bullpen, whose occupants would in turn transmit the information to the batter via a rudimentary semaphore system.

Thomson, now 77, more or less confirmed the story. "Sure, I've taken signs, obviously, in the not-very-nice way the Giants did it," he said. "But did it happen on that fateful pitch? No, it didn't. If you want to believe me, that's fine. If not, that's okay."

Branca said whether or not Thomson had the sign on the pitch in question is "irrelevant". "What I would like to know is could they have won without the signstealing?" he asked. "It wasn't illegal, but it was immoral."

Thomson said he felt "relieved" after his confession. "It was like getting something off my chest after all these years," he said. "I'm not a criminal - although I may have felt like one at first."

Having been semi-vindicated 50 years after the fact, the 75-year-old Branca said that he felt no animosity toward Thomson. Rather, he said, "I blame Giants' ownership and management for what happened."

The art of sign-stealing has its flip side. For one thing, just because a player knows what pitch is coming doesn't mean he's going to hit it. And, as teams try to make their signals undetectable to opponents, systems have become so complex that they often confuse their own players.

Sometimes, in fact, the missed signal can be more instrumental than the purloined one. In the 1984 World Series, Detroit catcher Lance Parrish anticipated that a San Diego baserunner would try to steal second, and signalled for a "pitchout" - a pitch deliberately delivered well outside the strike zone, in order to give the catcher a clear shot at throwing out the baserunner.

What Parrish hadn't taken into account was that Aurelio Lopez, the Tiger's pitcher, had the eyesight of Mr Magoo. As Lopez wound up and fired the ball, Parrish, by prearrangement, leapt up out of his crouch and took two steps to his right.

But Lopez, who had missed the sign, threw a fastball right down the middle of the plate. The only one more surprised than Parrish was the plate umpire, Larry Barnett, who took the rogue pitch squarely in the nuts.

Once he recovered, Barnett, to his credit, called the pitch a strike.