"A BOOK is like a trunk," explained the robust, middle-aged professor to his class, "tightly packed with things. At the customs an official's hand plunges perfunctorily into it, but he who seeks treasures examines every thread." In Lectures on Literature Vladimir Nabokov -- for it is he who leans over the lectern -- not only fingers every thread in some half-dozen novels, but also appraises the weave of the narrative and the pattern of the imagery, and with the eye of one who knows, points out the fine buttonholing in the first sentence and the satisfying zippering of the last.

Given annually at Cornell University from 1948-1958, these lectures were designed to introduce undergraduates to "Masters of European Fiction." Long-promised in book format, they are now presented -- posthumously, alas -- in two volumes, this one devoted to English, French and German writers, with a second due out next spring on the great Russians. Because Nabokov never ironed out all the creases and wrinkles in his nearly 2,000 pages of manuscript, the lectures needed some smooth editing and this was supplied by the notable textual authority, Fredson Bowers; the resulting book is something of a surprise.

After the success of Lolita (American edition, 1958) Nabokov moved to Switzerland, rented rooms at a Montreux hotel and grew inceasingly curmudgeonly in opinion, Olympian in pronuncement. What these lectures accomplish, especially in conjunction with Peter Quennell's recent Vladimir Nabokov: A Tribute (Morrow, $8.95), is the restoration of humanity to a writer who seemed to have traded his flesh and blood for an ivory tower. This Nabokov, the one drawing his diagrams on the blackboard in Goldwin Smith Hall, is as much art's passionate enthusiast as its cold practitioner -- the warmth of his own Timofey Pnin tempering the petitesse of the card-indes commentator of Eugene Onegin.

Oddly enough, the exuberant expertise of the Lectures on Literature most reminds me of Ezra Pound's humorous, iconoclastic The ABCs of Reading . Pound, making brilliant critical statements in his best Ol'Ez style, advocated close attention to a few key works and a particular focus on form; similarly Nabokov exalts fine-tooth reading, coupled with "a poet's patience and scholiast's passion." For Nabokov a great writer requires a great reader, one who completes the text, paying vigilant attention to details and patterns, actively accompanying the author as he plants and nourishes his images, themes and metaphors. Such a reader must feel "with his spine" the thrill of artistry, must be able to locate the adjective that ignites a description, must believe with Isaac Babel that "there is no iron that can enter the human heart with such stupefyin effect as a period placed at just the right moment."

In the analyses of Mansfield Park, Madame Bovary, or Swann's Way Professor Nabokov properly, though a bit harshly, scorns the human tendency to identify with a book's characters or to find ideas in the narrative. These are false critical practices, leading at their worst to a Charles Kinbote, that comic apotheosis of the bad reader, who discovers in the lines of Pale Fire his own history and misadvenures. To avoid this, one must instead "caress the details," so as to reconstruct exctly the world imagined by the writer. Nabokov consequently begins the discussion of a novel by correcting translation errors, drawing key diagrams on the blackboard (a beetle forKafka's "The Metamorphosis," the plan of Dr. Jekyll's house), and by setting forth the principal images and themes. These outlines, illustrations and corrections are among the most facinating pages of this facinating book, glimpses into the painstaking care behind the interpretive mastery. Like Henry James' ideal novelist Nabokov's ideal reader must also be one on whom nothing is lost.

And very little, it seems, got by Nabokov. He notes that Gregor Samsa's name is pronounced Zamza, and that Kafka's description suggests that the unfortunate young man is transformed into a domed beetle (not a cockroach). In 1904, he remarks, Leopold Bloom was one of only 4,000 Jews in an Ireland with a population of 4 1/2 million people; no wonder the hero of Ulysses felt lonely. How does Nabokov know these things? Quite simply because he has worked them out, or looked them up. He might well have called his critical method what he titled an essay on translation -- "The Servile Path." Specific information, he once asserted, is "the highest and to me most acceptable literary criticism." Indeed, Nabokov's antagonism to all "isms" and general ideas derives from his conviction that "they distract the student from direct contact with, the direct delight in, the quiddity of individual artistic achievement (which, after all, alone matters and alone survives)." As he notes in his talk on Mansfield Park , even "the color of Fanny Price's eyes and the furnishing of her cold little room are important." Some may scoff that such "triffles are not worth stopping at"; but Nabokov answers that "literature consists of such trifles."

Not surprisingly, the stress on the precise detail led this Cornell prof to set rather peculiar examination questions; one student recalls being asked to describe the wallpaper in Anna Karenin's bedroom. Students who supported a critical point with an exact and apposite quotation received a bonus of two points. Of course, Nabokov's class knew what to expect of a teacher who could remark that its members had "almost a month to reread Anna Karenin twice before the midterm."

From their foundation in the factual Nabokov's lectures gradually spiral up ward. Style, the inner structure of a book, mattered most. Naturally, the author of intricate constructs like The Real Life of Sebastian Knight and Pale Fire could speak of novelistic technique with indisputable authority, expertly picking out levels of narrative complexity. For instance, in his Bleak House commentary Nabokov invents the term "perry" to describe a character whose sole purpose is to witness an event so that it can be written about. Later he explains that Flaubert developed more elaborate techniques, such as the "counterpoint" used in the celebrated county fair episode in Madame Bovary . Rodolphe's flattery of Emma alternates with the announcement of agricultural prizes. A further refinement occurs in the complex synchronicity of Ulysses where some half-dozen events are taking place simultaneously. In all three cases, Nabokov modestly points out the limitations and advantages of the varying techniques, linking them to other elements of artistry in these "great fairy tales."

Nabokov's enthusiasm for literature, as his students Hannah Green and Alfred Appel Jr. recall in the Quennell volume, renews the passion for reading -- which also explains why nearly 400 undergraduates might sign up for his course. Moreover, the famous verbal playfulness leavens the punditry. In Bleak House Nabokov savors the subtle progression from the reverential "My Lord" (spoken to the Lord High Chancellor) through a lawyer's quickly uttered "Mlud" to the "mud" that oozes from the book's opening paragraphs. Likewise, Nabokov casually alludes to Lady Dedlock's "deadish wedlock" and to the "I of the story, it's moving pillar."

Such insights, though they may seem mere epigram or wordplay, nearly always illuminate a theme or character. Charles Bovary, observes the creator of so many love-lorn heroes, sees in his wife Emma all the romance and glamor that Emma yearns for in her dreams. Sometimes too, almost in spite of his theories of aloofness, Nabokov interrupts a cool examination to exclaim, for instance, that Dickens' Jarndyce is "one of the best and kindest human beings ever described in a novel," that "Dr. Jekyll and Mr. Hyde" yields "a delightful winey taste" or that Bloom taking breakfast to his wife is among the greatest scenes in literature.

Nabokov's faith -- that art resides in the details out of which the author constructs his imaginary world -- helps to explain his loathing for symbol seekers and for "the Viennese quack," that butt of the introductions to his Englished Russian novels.

Freudians, especially those who flourished in the '40s and '50s, often applied a standardized set of simplistic interpretations to the images of literature (a cigar equals a phallus); but as Nabokov reiterates "the abstract symbolic value of an artistic achievement should never prevail over its beautiful burning life," a life rooted in a carefully tilled fictional field.

For the same reason Nabokov here dismisses the historical interpretation of literature, along with biographical "human interest." The narrator of Swann's Way may be called Marcel, but his life is not Proust's. It is worth recalling, however, that Edmund Wilson, so much identified with the historical-biographical approach to literature, was at this time Nabokov's close friend and the man who persuaded him to add Jane Austen and Charles Dickens to his course list. (It seems oddly appropriate too that "Bunny" and "Volodya" should fall out over theories of translation, versification and editing; and more than ironic that Fredson Bowers, arranger of this volume, was the guiding force behind the editorial practices excoriated by Wilson in "The Fruits of the MLA.")

Because Nabokov assumes familiarity with the books discussed, these lectures are less introductions than brilliant afterwords, combining, the literature, "the precision of poetry and the excitement of science." They rightfully take their place with Flaubert's letters, James' prefaces and Woolf's diaries as privileged, nourishing, irreplaceable meditations on the art of fiction.