Louvish is at his best in discussing how Laurel and Hardy, unlike most of the great silent-film comedians, had no trouble making the transition to sound. Physical comedy, which had once seemed safe, even dreamlike, suddenly became painful when the sounds of the whacks and bonks were alarmingly present. Laurel and Hardy's films cleverly exaggerated the noise to cartoon level. A blow on the head became a reverberating gong, repeated in an echo chamber -- a comfortable laugh rather than an alienating shock.

Comedy duos have always been popular with moviegoers. The most successful ones pair two men who supply whatever is missing in their partners. There's a calculating one (Bud Abbott) and a naïve one (Lou Costello), or there's a handsome one who sings and gets the girl (Dean Martin) and a homely one who falls down and gets the audience (Jerry Lewis). Laurel and Hardy provide this contrast in visual appearance -- big versus small, fat Ollie versus skinny Stan -- but they were never compensating for each other by dividing up the assignment. Both were masters of enacting carefully controlled violence through brilliant physical comedy. They are a pair of equals, more like Bob Hope and Bing Crosby, a temporary team in six ''Road'' pictures. Hope and Crosby were both big stars who could sing, dance, get laughs and play romance -- a wised-up, sophisticated variation on Laurel and Hardy. Bing and Bob, like Stan and Ollie, could stand alone, but where Stan and Ollie usually worked together against hostile forces, Bing and Bob often competed against each other -- the Magic Johnson and Larry Bird of comedy duos.

Today, Laurel and Hardy do not receive the same adoration and scholarly attention given to Buster Keaton, Charlie Chaplin and Harold Lloyd. After a brief flurry of interest during the 1970's, they have more or less been returned to the shelf labeled ''fan favorites.'' It is said that no one loves them but the public, and it is true that they are not especially witty, emblematic or even sympathetic. They are just funny, very funny.

The ''boys,'' as their fans lovingly call them, are incompetent. Since they are no good at anything, they might as well take on the job of moving a piano across the Alps -- they do in ''Swiss Miss'' (1938). Over the years, they delivered washing machines (and pianos) to hilltop homes, tried to run a dancing school, changed into each other's pants on top of a skyscraper girder, got howling drunk more than once, joined the Foreign Legion and fueled a pie-throwing Armageddon that all other pie-throwings must be judged by. They have been body snatchers, air-raid wardens, process servers, chimney sweeps and street musicians (accordion and bassoon, playing ''In the Good Old Summertime'' during a snowstorm).

Everything Laurel and Hardy try goes wrong, but they never give up, seeming not to grasp the concept of failure. Their very incompetence becomes their most useful weapon for destroying the middle-class smugness that greets their efforts. The assault on the bourgeoisie is not uncommon in American comedy, but the boys, holding on to their hats, attack it with unparalleled passion, inviting the audience to join in and approve. Thus, they are not only our surrogates but also our best role models. No matter what befalls them -- and I have not mentioned the truly frightening women they often encounter -- they find new and fabulous ways to retaliate. My favorite is the egg placed under the victim's chin, after which the coup de grâce is delivered by snapping the chin rapidly down onto his chest. Watching this is like listening to Mozart.