AGNES DE MILLE confides in "Martha: The Life and Work of Martha Graham" that "at one point there was a long period during which I was on the outs with Miss Graham and wished to hear no more about her, to think no more of her problems." Martha Graham, in "Blood Memory," says, "at times, Agnes can say the absolute wrong thing, for the finest and most heartfelt reasons."They met in 1929. Graham, who died earlier this year, is now being celebrated in books that could be called companion volumes. Like their authors, their differences complement each other. De Mille's sincere, substantial biography takes the reader in hand and tells the story of a ferociously creative powerhouse in a strangely comforting way. Graham's memoir sometimes reads like an expensive souvenir program at a gala arts event, with anecdotes about everyone from Nureyev to the pope, but when she writes a bout her work, the ideas dance. De Mille spent some 25 years writing "Martha." She traces Graham's artistic development, almost a century's worth. Graham's early career - in Greenwich Village in the '30s, where American dance was being invented - was characterized by poverty. She performed in theaters borrowed from other productions on Sunday nights. She had a dollar-a-dress costume budget. Her dancers had day jobs. De Mille chronicles her rise to world acclaim, a later period of depression, and a rebound to superstardom. "Blood Memory" is like a scrapbook. Inspiring nuggets on Graham's creative process are tossed in with gossip, philosophical meanderings, and beautiful pictures. De Mille and Graham were from different dance worlds, but they shared a commitment to the theater. De Mille has been a ballet dancer and choreographer. Graham created a form of movement directly opposed to ballet. As she describes it in "Blood Memory": "I did not dance the way that people danced. I had what I called a contraction and a release. I used the floor. I used the flexed foot. I showed effort. My foot was bare. In many ways I showed onstage what most people came to the theater to avoid." This technique was not movement for movement's sake. It was meant to plumb the human psyche to its depths and reveal universal truths. To Graham, her work was as ancient as it was contemporary. "They say that the two primary arts were dance and architecture. The word 'theater' was a verb before it was a noun - an act, then a place," Graham writes. She and her dancers performed Greek myths and drew inspiration from American Indian rituals. In "Martha," dancer Jane Dudley tells de Mille that when she shared the stage with Graham, "Everything settled into place because, I believe, the stage was where Martha was at home. That was her proper sphere of action." De Mille shows us a character larger than life in both horrible and splendid ways, whose triumphs and excesses rival the Greek myths. Dancers who were devoted to Graham because she took them to new creative thresholds also told de Mille that Graham could fly into rages, lashing out at them verbally and physically. She was an artist whose dances won standing ovations, but she once had to be cajoled out of bed, where she hid because she had lost faith in a piece of work. She was able to perform into her 70s, but became an alcoholic and lost interest in her company and in life when she could no longer dance. Then she rose, phoenix-like, from a grave illness, and remade herself and her company. To read de Mille on Graham is to sense the forgiveness that kept her writing after she was "on the outs" with her. Agnes de Mille is also at home in the theater, and her prose, especially at dramatic points in the book, can sound like the narration from one of her uncle, Cecil B. de Mille's, epics. But her familiarity with theatrics both onstage and off serves her well. She exposes Graham's foibles only in quest of understanding, and interlards her remarks with reassuring little essays on art and artists . She cozily welcomes the reader into the theater, unlike Graham, who made it her crucible. She shows how Graham inspired a similar magnanimity in others. She always attracted the dancers, composers, and financial backers she needed to follow her vision. They saw her gift, they gave of themselves, and they forgave. Graham's sense of vision comes through in "Blood Memory" in a pungent retelling of "Night Journey," a dance about Jocasta and Oedipus. And in a 1944 letter to Aaron Copland, she wrote of the music that would become "Appalachian Spring": "It is so knit and of a completeness that it takes you in very strong hands and leads you into its own world. And there I am." Perhaps it was this willingness to go wherever inspiration led that made people think, as de Mille reports, that Graham was a goddess. She suggests Graham believed this at times, and one wonders if de Mille does, too. But she shows us the human Martha, whose triumphs are all the more poignant. In her efforts to understand and be fair, de Mille also gives us a multifaceted portrait of a friendship.