Playing on Heartstrings : RESONATING BODIES <i> by Lynne Alexander (Atheneum: $18.95; 230 pp.; 0-698-12039-7) </i>

Lynne Alexander, herself once a professional harpsichordist, has taken two characters (a talking cello and an aging English musician at the end of his long career), given them alternating chapters in which to tell the stories of their lives, and has thereby created something very like a piece of music itself in this wonderfully skilled, delightfully ambitious, and quietly moving novel (Alexander’s second, following the widely praised “Safe Houses.”

Nicholas Jordan is the musician, an internationally acclaimed baroque revivalist now 72 years old, troubled by ill health, and still tormented by his recent decision to retire from performing (“For the first time in his life, he had taken a safe, slow tempo in the Bach D Major. It was his cue to leave”). As the novel takes place, the uneasy Nicholas sits in the audience in the Salon d’Apollon at Versailles, listening to a concert in which his protege and chosen successor performs--doing so on the instrument that he has given her, the very instrument that he himself has possessed, performed on, and lived with for 50 years.

And what an instrument it is--or she is--speaking to Nicholas as the concert proceeds, and listening to his thoughts in return. She’s not really a cello at all, but, as she tells us, “I am Rose, Viola da Gamba, of the family Viols, noble in size and shape. Like the cello, I am held between the legs: da gamba . Unlike the cello, however, which often has a metal tail on which it leans (causing unsightly damage to wooden floors), I rest on nothing but the inner calves, and to these I transmit my full sonority.”

Rose’s story alone (hold the miracle of her voice for later) is a thing beguiling. It’s a story unobtrusively told by Alexander--from Rose’s beginning in 1670 in the Paris workshop of Christophe Bernard. He created her, the most lovely of the seven-string viols, as a wedding gift for his wife; she, however, died in childbirth before Rose’s completion. Beautiful, modest, touched from the start by love and by her awareness of mortality, Rose made her way through the next two centuries, had a piece composed in her honor (the lost “Apotheosis of the Bernard Viol”), was played by the loathsome and puritanically repressed Cornelius Graswinkel, was painted by Vermeer and owned by the pudgy and passionless Roger North in England. She found her way to the French court where she was played at Versailles by the brilliant Marin Marais, later by the demonic genius Antoine Forqueray--all of this (and more) in a life’s journey that was to see her barely survive the fiery cataclysm of the French Revolution, find her (out of fashion) moldering first in a museum and then in a pawn shop in Paris. Her discovery there by Arnold Dolmetsch would lead at last (after still more confusion, adulteration, and abuse) to her being bought at an auction in London by one Harry Jordan for his passionately desiring 12-year-old son Nicholas.

And who was this strange, only child of odd parents (his father was to disappear forever soon after buying the viol), with his single-minded passion to have, and play, Rose? He was, to put it plainly, her lover and savior, as she was his. His love for her (“his Rose, who . . . responded to the lightest touch. How he loved her, her smooth surface, the hollow depths of her, the delicate contours of her body”) was equal only to hers for him (“Mount me, hold me, string me, tune me”)--and between the two of them, these resonating bodies would be created, again and again, through great passion, the wonder of enormous beauty, not to mention huge renown and material success (“Imagine,” says Rose at one point, “Forqueray at the top of the hit parade”).

And what is the real question the novel takes up? Alexander’s graceful learnedness, subtlety, and range--as well as her humor and shrewdly penetrating eye--allow questions galore to come up, but at the heart of it all lies a tale about the human cost of the life lived for beauty. The past of Nicholas Jordan, after all--as he realizes while sitting uneasily in that concert at Versailles--was in many ways a lost and even a destructive one in his half-century devotion to Rose. “He had put mother, father, students, lovers, wife and child second to her in his affections. . . . He . . . had cut himself off from human intercourse in order to become one with her.”

The heart of the novel, of course, lies in Nicholas Jordan’s effort to make a meaningful peace with the long trail of failure and success that now lies behind him--and with the death he knows to be approaching. But what raises this story toweringly above the commonplace is the unmatchable character of the wonderful Rose, who offers counsel, perception, wisdom, and corrective advice throughout, and whose unflappable and enchanting voice will be a high treasure for lovers both of music and of words. Nicholas will die, while Rose will go on, played by others, and yet even so she can still give comfort for what has been, and can advise Nicholas to “Be grateful for the adventure and say goodbye.” “I am uniqueness and beauty personified in an age of uniformity and ugliness,” she reminds him, and, in words that can thrill as meaningfully and deeply as any others in this unpretentiously profound and quietly daring masterpiece of intelligent, thinking fiction: “Close your eyes and let me caress you for the last time. Listen to my voice, which resembles the human in all its inflexions . . .; clean and piercing in the treble, caressing in the tenor, ravishing and golden in the bass.”