TWO OF THE MOST difficult tasks which a novelist can set himself are to write an erotic novel and to deal convincingly with the supernatural, and a writer who attempts both in the same book, particularly when the attempt marks a new direction of his talent, at least deserves an accolade for courage. But Richard Adams, author of Watership Down and The Plague Dogs, deserves more. With A Girl in a Swing we acclaim success.

The story is told by Alan Desland, sitting alone in his Berkshire house on a windy July evening in the early weeks after the death of his young German wife and recalling with pain and anguish the history of their meeting, courtship and doomed marriage. The tragedy has its roots in his own early life, and those formative years, the happy childhood with his older sister, his schooldays at Bradfield where he first becomes aware of his disturbing psychic powers, are beautifully described. Before meeting the girl who becomes his wife he is a likeable, fastidiously detached, conventional Englishman, a conforming Anglican who is as untormented by religious doubt as he is by sexual desire and who, convinced of his physical unattractiveness, finds in his growing love and understanding of fine porcelain a compensation for the sterility of his emotional life.

And then, on a business trip to Copenhagen, he meets a beautiful typist, Kathe Wassermann, and the whole of life is changed for him. He is astounded by love, enchanted by her beauty, her hedonistic charm, her highly individual grace, drowned in a vortex of new and ecastatic sensations. He is intrigued, too, by an ambivalence he detects in her, a mixture of innocence and a pagan ruthlessness. Knowing nothing about her except that, miraculously, she returns his love, pressing no questions on her, he proposes and is accepted. Shortly after his return home she comes to him, still without explanations, and they are married, although to his slight dismay she is adamant that there be no religious ceremony.

The marriage, and the response which Kathe's lovemaking awakes in him, transform his life. Before Kathe he was psychologically maimed. Now, through the power of erotic love, he is made whole. His friends, enchanted by Kathe, share his happiness. Only his mother, hurt by his reluctance to confide in her, holds aloof from this new and mysterious daughter-in-law.

But then the terror begins and, like the Hound of Heaven, its footsteps beat ever closer. Its manifestations are both supernatural and human; a child's voice weeping over the telephone, the illusion of a drowned corpse in the green depths of the pool where they swim. Kathe's inexplicable bouts of crying and terror, the nightmares which rack them, a black dog whose name is death. Gradually the reader, like the narrator, comes to an understanding of the truth about Kathe and the inescapable doom which she carries with her.

The action of the novel is geographically wide, ranging from the gentle uplands of Berkshire to Copenhagen and Elsinore and the forest swamps and river springs of Florida where the couple go for their honeymoon. As one would expect with Richard Adams, the sense of place is brilliantly evoked, enhancing and reflecting the mood of the characters and the thrust of the action. The book is rich in symbolism and the potent if conventional sexual imagery of flowing water cascades through the noel, in the descriptions of the locations, in the smiles Desland uses when describing his and Kathe's exultant lovemaking, in the dripping terror of their nightmares as the unthinkable draws ever nearer. Their doomed marriage is belatedly consummated beside a stream, and Kathe's tragedy ends as it began on the seashore in a climax of terrifying power.

One cannot expect a novel which deals with the supernatural, even when the characters are themselves rooted in reality, to provide the neat and logically satisfying explanations of a detective story. But I should like to have known something of Kathe's past, to have been given some clue to the reasons which led her to accept Desland in the first place and then to pay such an appalling and unnatural price for the love and security which marriage with him offered. He tells us that she is beautiful, and this overwhelming physical attractiveness, the erotic charge which sets him alight, is no eccentric individual response; others feel it too. Apart from her numinous beauty, Kathe is capable, talented, intelligent and sexually highly skilled. She knows that Desland isn't a wealthy man and she must have met more attractive potential partners. The deed which lies at the heart of the book's haunting tragedy is so horrible, at once a symbol of evil and its manifestation, that I felt the need to understand something of the desperation, the moral corruption or the yearning for security from which it sprang. But the reviewer has to remember that the response to a work of high imagination is uniquely personal. There may be readers for whom this reticence about Kathe's motives and the details of her past life provides an intensification of the mystery which surrounds her; the horror is rendered more horrible because we can only guess at the psychological springs from which it flows.

For any reader the success of The Girl in the Swing must depend on his response to the two chief characters and the relationship between them. But the subsidiary characters are excellently drawn, particularly the staff of the family shop, Mrs. Taswell, Deirdee, and old Miss Lee. The growth of Desland's interest in the family business from the small boy's wonder at the pretty, bright-colored china objects to the adult's appreciation of ceramic antiques and fine modern porcelain is beautifully handled. For me the least successful character, although an important one, was Tony Redwood, the local vicar whose rational and accommodating faith is no match for the primal pagan mystery which is Kathe. And in the end Desland looks for his salvation, not to the old conformities but to his enduring and symbolic obsession.

"Clay scrabbled out of the dungy earth, mixed with water, with sand, with flint, with ashes of bones; kneaded, caressed and moulded by patient hands; fired in the kiln and put to work to ease our lot, to add comfort and a little style to our necessity to eat, to drink, to wash, to excrete; or set up simply to be admired, like music, for our dignity and pleasure; and, like our own flesh, doomed at last to be shattered and discarded, rubbish trampled back into the ground whence it came. What else thus bodies forth the nature of life and manifests, from the finite, the infinite?"