His Excellent English Adventure : DARKEST ENGLAND by Christopher Hope; W.W. Norton; $25, 304 pages

Mark Twain must be kicking himself in his grave. He could have written this novel back when England was a bigger and juicier target. True, “A Connecticut Yankee in King Arthur’s Court” spoofed contemporary as well as medieval Britain, but to do what Christopher Hope has done here--to twit the empire-builders in their own pith-helmeted style--was an opportunity Twain regrettably let pass.

Hope, a South African novelist and poet (“Kruger’s Alp,” “The Love Songs of Nathan J. Swirksy”) has a wickedly simple idea. He sends one of the few surviving members of the San people, or Bushmen, on an expedition to . . . darkest England, bearing a paper dated 1873 on which the “Old Auntie With Diamonds in Her Hair” (Queen Victoria) had promised to protect them from the Boers and other oppressors “like a Lioness her whelps.”

David Mungo Booi, named for two of the 19th century explorers (David Livingstone and Mungo Park) whose success he hopes to emulate, flies to London at the behest of the tribal Society for Promoting the Discovery of the Interior of England. His mission: to ask the present queen to honor the promise by sending her “tall soldiers in red frocks” to punish the Afrikaners again.

Booi is also supposed to assess the suitability of England for settlement by Bushmen. Other questions need answering: Are the natives friendly? Will there always be an England, as the English claim? Did they really build Jerusalem in their green and pleasant land?

Wearing a leather codpiece, a new suit and rubber boots, bearing trinkets for trade and journals in which to record his observations, Booi is promptly arrested and nearly deported. Rescued by a radical clergyman, he is spirited to the countryside, where his pilgrim’s progress resumes.

The England that Booi discovers is a damp depressing place whose people aren’t coping well with economic and political decline. They are sunk in resentment, superstition and xenophobia. They alternately treat the diminutive Bushman as a pet and view him with fear and loathing.

Before he finally gets to Buckingham Palace, Booi encounters rapacious aristocrats, hostile slum dwellers, militant animal lovers, soccer hooligans and hippies on the dole. He sees the inside of a jail, an insane asylum and Parliament. He wins the love of the clergyman’s repressed daughter (whose conspicuous buttocks, a source of shame in England, are marks of beauty among the Red People of the Karoo) and is chased cross-country by fox hunters intent on killing him.

Hope’s satire works in two sometimes contradictory ways. Sometimes Booi is an innocent abroad. He humbly takes the English at their word--believing the police, for example, when they call the jail a “royal guest house.” He puts sophisticated observations in comically primitive terms:

“When faced with some present or future event they find unpalatable,” he notes, the English “lift their noses to give the most marvelous simulation of ignorance. . . . I have noticed something similar in the behavior of black bush pigs when faced by the ravening hyena. . . . The hyena may murder the pig, but the victim never condescends to notice.”

Elsewhere, Booi speaks, as the English explorers did, in full confidence that his is the superior culture--though he is usually too nice to tell his hosts so. “In my estimation, the reintroduction of these people to the essentials of true polytheism is possible,” he sighs. “It can be done. But it will take many years. Missionaries. Dedication.”

Ultimately, the test of a funny book like this is how serious it is. “Darkest England” lacks something of Twain’s savage glee, but it’s full of barbs nonetheless. Hope isn’t content with detailing the unwholesome diet and odd sexual practices of the English; he finds even their impulses to do good sinister--”Once set upon that path, they are merciless”--and links their current hypocrisies with the sins of their glory days, when the Bushmen were nearly exterminated. It’s more than just a matter of kicking a little country when it’s down.