WHEN NOEL COWARD wrote "Mad Dogs and Englishmen" in 1932, the instant popularity of the song's irreverent lyrics was a sure indication that the idea of Empire was well into its death throes, and that the old confidence that the rule of the white over other races was according to nature and therefore good, was more risible than right. The Boer War had injected into the British mind the first uneasy questioning of colonialism, and the Great War had left the colonial powers of Europe too exhausted to do much more than administer their possessions with what wisdom in them lay. Valerie Pakenham has taken as her subject the short period between these two wars and the last generation of "Expansionists" who found themselves running (in perpetuity, as it then seemed to most) not only India, Burma, Ceylon and other parts of the old Empire but also enormous hunks of tribal Africa added to the Crown by the mad, disreputable "Scramble for Africa" during the last 20 years of the 19th century.

Pakenham has chosen to relate the events of this short period through skillfully interwoven biographical accounts of its leading figures -- administrators, soldiers, missionaries and traders. Not all have remained household names into our own times, but Pakenham uses the accomplishments and misadventures, letters, diaries and reminiscences of famous and obscure alike to point up the growing lack of interest in the Empire at home and the increasing irritation of the men abroad at the ignorance and pennypinching interference of their masters in Whitehall. I am old enough to consider the first two decades of this century the recent past, yet every page turned added to the conviction that my father spent his youth quite literally in another world.

Try imagining a world where Marx, Nietzsche, and Freud were still confined within the walls of academe, nihilism was merely a newly minted term, and relativism not yet amok in sleepy suburban streets! Cynicism there was in plenty; boredom, venality, aggression and politicking in and out of season, much as today. But Lytton Strachey and his admirers were still in the future, the ordinary citizen still considered heroism laudable rather than neurotic, the military life was envied, trade was socially unacceptable unless on the grandest scale and in faraway places, the family was sacred, and the white man obviously God's gift to "lesser breeds without the Law." As we know now, threatening fissures had already appeared behind the complacent facade of European supremacy, and in the East "Indianization" had led young, middleclass Englishmen to abandon careers in the Indian Civil Service or Indian Army to try their luck in Africa's new territories. Yet the men, and the very few women included, appear to have been oblivious of the undermining of their world. They took off by the dozens to bring order, trade, industry and Christianity to every part of Africa, to Malaya, China and the East Indies. With small hindrance from conscience or country, they embarked on numerous small wars, defined as "wars against the uncivilized and the barbarian," and often conducted according to a military manual that reads like a handbook of cricket played with bullets, not balls. They also, however, made unwilling peace among warrior peoples who had never known that state before. They slaughtered game everywhere with joyful abandon, but -- though ignorant of conservation as such -- before long and for sheer affection for the animals, instituted systems for licensing or forbidding hunting for which we today owe them something.

THEY DEPOSED monarchs and elevated princelings with foolhardy self-confidence, yet seldom suffered for their temerity. They partitioned territories or attempted to weld together ethnic enemies with an historical disregard from which Africa still suffers. They built roads and railways, hospitals and schools, canals and harbors and elaborate courthouses with equal enthusiasm and, with few exceptions, loved their work if not the conditions in which they did it, and displayed a genuine though patriarchal affection for the people they saw themselves as serving. None doubted the wisdom of their atttempts. Inner questions were left to the few intellectuals among them, notably Leonard Woolf, Joyce Cary, and (later) George Orwell. Even so, Woolf, that most anti-imperial "bounder," could write in later life that had he not met Virginia Stephen he would have chosen to immerse himself forever as a district officer in Ceylon, married to a Singhalese wife, while Cary, who conducted an unending war with his superiors, finally left West Africa only for the sake of his wife -- and then set his first few novels in that country. Neither foresaw, for all their insight, how soon the end would come.

For a generation after the fatal shot rang out in Sarajevo, young Britishers rode, walked, or bicycled their territories from Barbados to Brunei, fostering the continuance of ideas and a way of life already gone at home. What becomes apparent as the book progresses is not so much the underlying social Darwinism inherent in the idea of Empire (though that is clear enough), as the inventiveness of the sliding scale of democratic principles applied in such highhanded, paradoxical fashion to such a diversity of cultures. At the end, Pax Britannica, despite its many mistakes and hypocrisies, remained a more immediate reality to the ruled than the rulers, who seem, in retrospect, to have been almost too hasty in shedding their responsibilities.

It takes no very sensitive teeth to grate at George Santayana's Wide World Magazine sentimentality when he writes: "Not since the heroic days of Greece has the world had such a sweet, just, boyish master." But a glance at the old red areas on the globe, now so vari-colored, makes it easier to agree with him as he continues: "It will be a black day for the human race when scientific blackguards, conspirators and fanatics manage to supplant him."

Valerie Pakenham's fine sense of the past allows her to achieve moments of irony without ever descending to belittlement. The book is furnished with excellent photographs, a bibliography, notes and index. Best of all, it reads with admirable ease and pace.