MORE BRITISH STUFF UNKNOWN IN AMERICA: Bubble and squeak. Zebra crossings. Trifle. Trainspotters (America has "rail fans" but British trainspotters carry it to a whole higher level-or lower level, depending on your point of view). The Monster Raving Loony Party (See http://freespace.virgin.net/raving.loony/ ). Pickled onions. Paté. The red "L" (for "learner") on car bumpers. Private Eye (see http://www.private-eye.co.uk/ ). Fireplaces in pubs-they really work! CAMRA (see http://www.camra.org.uk/ ).

MORE AMERICAN STUFF UNKNOWN IN BRITAIN: Yearlong political campaigns. TV evangelists. (Is it true that in Britain it's illegal for religious groups to solicit money on TV or radio?) Automatic transmissions (at least far more common in the US than Britain). Automatic chokes (most Americans wouldn't know what to do with a manual choke if they saw one). "English muffins."

ROUNDABOUTS: I've heard that some east-coast American cities have them, only they go counterclockwise (anticlockwise) and they're called traffic circles. They're unknown elsewhere. In Britain, they're more common than traffic lights. They make sense, since they keep traffic flowing more smoothly than traffic lights, but they require a mastery of rules and driving skills that baffle most Americans until they get used to them.

HEDGES: In America, they're just ornamental rows of shrubbery, planted for purely aesthetic purposes. Most Americans aren't even aware that in Britain they have (or had until recently) a practical purpose: they're literally living fences, meant to confine livestock. To serve this purpose they have to be carefully maintained. People prune them and interweave their branches to keep them strong and tight. Some hedges have existed since time immemorial. Sadly, farmers now often pull them down to make larger fields, or replace them with barbed wire, which takes up less space and is easier to maintain, but I believe there are societies devoted to preserving ancient hedges.

While we're on the subject of horticultural practices: does anyone know, or care to know, what a coppice is? Or a pollarded oak? An espaliered apple tree? I'm full of arcane lore!