LONDON - With a determined step, the young American tourist mounts his small, portable ladder on the edge of Hyde Park and booms: "I'll reply to that."
The challenge is directed at a small man atop another ladder a few yards away which bears a yellow wooden sign saying, in red letters, "Socialist Party, Clapham."
Suddenly the latter's Marxist diatribe, delivered in a thick London accent, is overwhelmed by a sermon on the merits of the free-market economy delivered in articulate tones by a passing American.
The miffed, out-talked comrade picks up his party sign, wraps it in his raincoat and leaves. The socialists of Clapham have ended another rally.
The crowd whoops its appreciation at the scene on a Sunday at Speaker's Corner, a famed citadel of free speech in London's Hyde Park that's just a strip of land between the parks' green lawns and the city's roaring traffic.
Each Sunday, at what used to be a site for public hangings, soapboxes and portable ladders are deposited as rostra for the vanguards of free speech.
Since 1783, anyone and everyone has had the right to get up and politically harangue, deliver religious thunderbolts, rage about social injustices, or simply entertain. Just two thing are taboo: swearing, and insulting the queen.
Speaker's Corner is still a lively place, equal to its fame as a symbol of British liberal tradition.
It is, of course, a tourist draw. And it also draws another species in a way just as eloquent as many a speaker - and often more so than most: the heckler.
Ron Bowden is one such artist. For 20 years he has been coming to the Corner and is today a master of the stabbing, quick-witted remark - the sort that deflates speakers to the point of giving up.
Bowden knows all his adversaries. Most have been coming to the corner for years. "Like him over there in the blue baseball cap," he says. "That's Martin."
Martin, he explains, climbs his little portable blue ladder mainly to extoll his own virtues - and also to impress the ladies. And that makes him a fair, and regular, target for the hecklers.