TOM SHARPE's chronicles of Henry Wilt have attracted something of a cult in his native Britain, but he has yet to attract much of a following on this side of the pond, a deplorable situation that the present publication of Wilt on High should do much to dispel.

Sharpe is a masterly practitioner of what one might call Tory humor, although it only incidentally has to do with politics and is by no means exclusively British in provenance; American practitioners of the genre have included Mark Twain and W.C. Fields. It is a form of humor based on a single iridiscent rather than blinding insight, to wit: the lunatics have seized control of the madhouse and reasonable folk everywhere are at their mercy, a proposition with which I find it hard to argue, at least while Congress is still in session.

As we join Wilt at the beginning of his latest misadventure, he has risen to the headship of the department of liberal studies at the Fenland College of Arts and Technology. Let's listen in.

"As far as Wilt could see, the whole thing had been counter-productive and as he expressed it, if anyone was being exposed to anything, the lecturers were being exposed to the collective barbarism of (their students) which accounted for the number who had nervous breakdowns or became milkmen with degrees. And his own attempt to change the curriculum to more practical matters, like how to fill in Income Tax forms, claim Unemployment Benefit, and generally move with some confidence through the maze of bureaucratic complications that had turned the Welfare State into a piggy bank for the middle classes and literate skivers, and an incomprehensible and humiliating nightmare of forms and jargon for the provident poor, had been thwarted by the lunatic theories of so-called educationalists of the sixties . . . and the equally irrational spending policies of the seventies. Wilt had persisted in his protestations that Liberal Studies didn't need video cameras and audio-visual aids galore, but could do with a clear statement from somebody about the purpose of Liberal Studies."

IT SHOULD be apparent from the foregoing that such writing requires a clear if baleful eye, a controlled awareness of the outrages inflicted by ordinary life, and a narrative mind swimming forever and valiantly against a competing logical system that needs, as they say, no introduction; the experience is not unlike reading science fiction about the present. Wilt arrives equipped with a quartet of appalling prepubescent daughters and an exomorphic earth mother of a wife who immediately proceeds to poison his beer with aphrodisiac, and he shortly acquires a shadow in the form of the chief of the local narcotics squad, a maniac who believes his unwitting quarry is leading him to the lair of a criminal mastermind. Up to this point, and despite a few loose ends (such as why Wilt remains married to the wretched woman), the book is a sockdolager that fairly begs to be read aloud. Great stuff, this.

It fails, I think, because of three surprisingly commonplace mistakes: a curiously British notion that there is something inherently uproarious about male genitalia, a compulsion to arrange a finale of surpassing hilariousness in the manner of a West End farce, and a by no means exclusively British belief that once you know a foreigner's nationality, you know something useful about him.

Wilt on High ends with a colossal ball-up at a nearby American Air Force base; I'm sure we'll all admit that there are few things funnier than an American. (A minor point. There is no such rank as corporal in the USAF.) The confrontation has its moments -- Sharpe is too talented and generous a writer to blow completely even the most unpromising of material -- but I guess you had to be there. The wonder is that the book actually survives the experience, rather like a favorite uncle in his cups. No matter what he does now, only a few moments ago he was absolutely marvelous.