$ EFORE THE TRUMPET; Young Franklin Roosevelt, 1882-1905. By Geoffrey C. Ward. Harper & Row. 390 pp. $19.95.

IT SEEMS that Geoffrey C. Ward has attempted, in Before the Trumpet, to do for the Hyde Park branch of the Roosevelt family what David McCullough, in Mornings on Horseback, did for the Oyster Bay branch: to portray the celebrated family out of which a presidential Roosevelt emerged, and to describe the early stages of that emergence. He has had considerably less success than McCullough, though, in part because of his own shortcomings but in larger part because the story of Franklin Roosevelt's family and youth is in almost every respect less interesting than the story of Theodore Roosevelt's. Ward is up against dramatic deficiencies that would defeat just about any storyteller, and he hasfailed to overcome them, even though he has produced a substantial amount of original research that is not without its own value or interest.

Franklin Roosevelt may well have been a more effective and influential president than Theodore, but Theodore had by far the more sensational -- the word is used advisedly -- life. The story of Teddy Roosevelt's early years, as has been splendidly demonstrated both by McCullough and by Edmund Morris in The Rise of Theodore Roosevelt, is loaded with excitement both actual and psychological: his upbringing in a large, loving, tumultuous family, his terrible fight against asthma, his self-willed metamorphosis from a skinny weakling to a bulky he-man. Franklin, by contrast, was an only child who grew up utterly shielded from life's harsher realities, who did not flee the nest until his mid-teens and then into the protective embrace of Groton, who seems to have had no adolescent crises of a genuinely crippling or transforming nature.

There simply isn't much of a story in FDR's early years. Not until polio struck him in 1921, a decade and a half after the conclusion of Before the Trumpet, did his life acquire real drama and urgency; until then he seemed nothing so much as an amiable young man of modest abilities and excellent connections. So Ward has the problem of fabricating a rather large book out of what is a rather small amount of important material, a problem he attempts to solve by telling us a great deal about Roosevelts other than Franklin. He does this with such determination that FDR himself, after a brief preface, does not appear in his own book until more than a hundred pages have been exhausted.

These pages are devoted primarily to his father, James Roosevelt, and his mother, Sara Delano. We already have a voluminous amount of material on the latter, and Ward does not add appreciably to it except to paint an agreeable portrait of her large, happy family and its beloved Hudson iver mansion, Algonac; he goes on at some length about her father's involvement in the opium trade, which is diverting but not especially pertinent. On James Roosevelt he is more effective, primarily because he makes a persuasive case that FDR's father was not so subordinate to the much younger Sara as he is generally protrayed; the James Roosevelt whom Ward gives us is a "genteel gambler" with a "heady sense of risk and adventure," and a close companion to a son who loved and admired him.

When at last little Franklin appears, on January 30, 1882, it is after a long and painful labor that, Ward speculates, "may have had much to do with the extraordinarily powerful bond between mother and son that was forged during the first moments of Franklin Roosevelt's life and that remained intact until the last instant of hers." Whatever its origins the bond certainly was a strong one, as has already been quite sufficiently documented elsewhere; in the circumstances it is something of a miracle that FDR never became wholly a momma's boy, and a tribute to his innate grit that he spent much of his life fighting -- fighting quietly and politely, but fighting -- against the potent emotional inducements his mother dangled before him.

EVEN WHEN YOUNG Franklin went off to Groton and then to Harvard his mother was there, either in spirit or in fact; she set herself up in a Boston flat during the academic year and tried, with only limited success, to keep a tight hold on the apron strings. But Franklin was determined to prove himself a man among men, an effort that itself had only limited success. He was a dismally ungifted athlete, no ticket to popularity among the muscular Christians of Groton, and he made too transparent an effort to ingratiate himself with his peers, which may well have accounted for his rejection by Porcellian at Harvard. This rejection was as close to a serious crisis of youth as he came; Eleanor Roosevelt thought it gave him "an inferiority complex" and "helped him to identify with life's outcasts," but a more likely interpretation is that it gave him a fierce determination to prove himself. As Ward writes:

"There were those among FDR's political enemies who would later charge that a desire for personal vengeance upon the wealthy and exclusive young men who had rejected him at Harvard lay behind many of the New Deal measures that made them denounce him as a traitor to his class. This is a simplistic and remarkably complacent explanation, of course, but the rejection must surely have reinforced Franklin's growing fascination with politics and power. First at Groton, now at Harvard, he had learned firsthand that admission to what his future wife called 'the inner clique' was not automatically conferred, even upon a Roosevelt. He became 'extremely ambitious,' (a friend) recalled, wanting above all else to become 'popular and powerful.' He would never againexclusively rely on position and congeniality to get ahead, would no longer depend upon others to notice him; instead, he would do his energetic best to carve out a constituency of his own."

From Harvard it was on to cousin Eleanor and marriage, after what seems to have been a brief and insufficiently documented romance with a young woman in Boston. Ward retells the familiar story of Eleanor's miserably unhappy childhood and her consuming devotion to her father, Elliott Roosevelt, the feckless wastrel whom she imagined to have been a great man. To this and all else that we already know he adds a couple of usefully cautionary points: that Eleanor, though no beauty, was scarcely the ugly duckling we usually imagine her to have been, and that given her close kinship to the president of the United States, it was Franklin rather than Eleanor who could be said to have gained through the marriage.

Ward has earned these and other insights through deep immersion in Roosevelt family papers and other documents that previously had escaped the attention of biographers and historians. What these documents tell us may be interesting at times, but remarkably little of what they tell us is new. Ward has done hard work, but he has altered scarcely a hair in Roosevelt's portrait as already painted by Frank Freidel, Arthur Schlesinger Jr. and other biographers. Neither has he managed to locate a narrative line for his story, which jerks along, in unexceptionable if uninspired prose, from person to person and event to event. Before the Trumpet is certainly a good-faith effort, but good faith is not always enough.