Nabokov as professor: an enviable experience; Lectures on Literature, by Vladimir Nabokov, edited by Fredson Bowers. New York: Harcourt Brace Jovanovich. $19.95

Style and structure are the essence of a book. Great ideas are hogwash. Let us not kid ourselves: Let us remember that literature is of no practical value whatsoever, except in the very special case of somebody's wishing to become, of all things, a professor of literature.

These admonitions were spoken in the playful, smug, Olympian voice of Vladimir Nabokov to the students of his "Masters of European Fiction" class at Cornell University. The voice of the lectures is familiar to Nabakov readers; it is the voice of "Strong Opinions," the medium for beautifully and often critically turned phrases, for haughty maxims, for mockery. It is the voice that could set wriggling against the wall the likes of Faulkner, Mann, and Dostoyevsky.

Even those who don't know his work well remember Nabakov as the emigre Russian aristocrat, the child of parents who loved literature, the young man who fled revolutionary Russia for Europe and eventually Europe for America. He is probably most famous for his novel "Lolita." But he authored so many more fine and dazzling narrative pieces in both Russian and English, among them "Pale Fire." He taught at Cornell and Wellesley and then lived in Montreux until his passing in 1977.

This collection of lectures/essays, the first of two projected volumes, takes as its subjects Jane Austen's "Mansfield Park," Dickens's "Bleak House," Proust's "Remembrance of Things Past," Kafka's "The Metamorphosis," Flaubert's "Madame Bovary," Joyce's "Ulysses," and Stevenson's "The Strange Case of Dr. Jekyll and Mr. Hyde."

Nabokov's method: "to caress the details, the divine details" -- all of them, as indicated by the reprints here of his heavily marked texts and the diagrams he painstakingly drew for himself and the class in order to visualize a character's world. The gardens at Mansfield Park, for instance, diagrammed so that we may better understand the pattern of strolling couples that so frustrated and saddened Fanny Price. Or the "gorgeous, mauve-colored orchid" that must have been the model for the cattleya that haunted Proust's Monsieur Swann.

"We must see things and hear things, we must visualize the rooms, the clothes , the manners of an author's people," insisted Professor Nabokov. "The color of Fanny Price's eyes in 'Mansfield Park' and the furnishing of her cold little room are important."

Still more important were the details of plot and design. As Nabakov put it, "My course, among other things, is a kind of detective investigation of the mystery of literary structures." In class he seems to have been a genial, almost gentle sleuth. He would examine the illusion of the fictional world from the inside,m impressing upon his students "such combinations of details as yield the sensual park without which a book is dead."

Nobokov believed wholeheartedly in enchantment; he once proclaimed that all great novels must be, first, great fairy tales. In his own work such enchantment extended beyond the realm of fiction to what is arguably his finest conjuing of all, his autobiographical "Speak, Memory." The enchantment is again present in these lectures. Nabokov's "vehicle?" His ubiquitous metaphors for the relationship between reader and writer, writer and world:

"Up a trackless slope climbs the master artist, and at the top, on a windy ridge, whom do you think he meets? The panting and happy reader, and there they spontaneously embrace and are linked forever if the book lasts forever."

Or: "It seems to me that a good formula to test the quality of a novel is, in the long run, a merging of the precision of poetry and the intuition of science. In order to bask in that magic a wise reader reads the book of genius not with his heart, not so much with his brain, but with his spine. It is there that occurs the telltale tingle even though we must keep a little aloof, a little detached when reading. Then with a pleasure that is both sensual and intellectual we shall watch the artist build his castle of cards and watch the castle of cards become a castle of beautiful steel and glass."

Some of these lectures don't translate well to published form. The "Ulysses" piece (without the usual classroom interruptions) seems too long, too mired in plot summary, and there is no professorial presence to rescue it.

Yet there is much in this volume that should not be missed, much that is of sheer delight and entertainment. Read thi s and envy Professor Nabokov's students.