YOU ARE LYING under a multi-colored beach umbrella, watching the surf rolling in. People are all around you -- some slathered in oil like broiler chickens twirling on a spit, others running to and from the sea, some ritually throwing Frisbees back and forth. But this late summer noise and confusion is merely background hum to you because you're tucked into another world. Earphones on, you're lost in the sonic bliss of your beach cassette.

Beach cassette? Well, why not? If there are beach books, why not beach tapes -- recorded books you tuck into your bag for vacation listening. Beach tapes also have a slight advantage over books: You don't have to wait until you actually get to your vacation spot to begin your escape into literature. The adventure begins in your car's cassette player as you roll the long miles to your destination.

You might, for example, ease the tribulations of driving through weekend traffic -- a circus of human aberrations at best -- by listening to neurologist Oliver Sacks read selections from his best seller, The Man Who Mistook His Wife for a Hat (as you watch your fellow motorists mistake their cars for guided missiles).

Sacks, in a precise and humane narration, recounts the strange story of Dr. P, a music teacher whose malfunctioning brain presented the world to him as a bizarre visual patchwork. He saw familiar people as objects or didn't recognize them until they moved and even occasionally mistook his foot for his shoe. None of this robbed Dr. P of his love of life, his humor or his passion for music -- which Sacks sees as his patient's spiritual salvation.

In the second case we meet Witty Ticcy Ray, a victim of Tourette's syndrome, a neurological disorder which produces tics, unpredictable explosions of movement and verbal outbursts. But when Sacks discovers that Ray is exquisitely receptive to a drug that can control this extraordinary ailment, both doctor and patient also realize that the symptoms of the disease actually enhance aspects of Ray's creative life. Ray wants normal health, but not at the cost of his wit and personality. How Sacks and Ray reconcile this dichotomy makes for fascinating listening.

While the actual facts of these cases and Sacks' prose are arresting, it's ultimately the author's voice and delivery that make the tape compelling whether you've read the book or not. When Sacks discusses The Twins, for example, the idiot savant brothers who live in a mysterious world of numbers-as-music (they croon to each other in dialogues of 20-digit prime numbers), what might have been merely clinical becomes lyrical.

I doubt that any other narrator describing how The Twins are finally separated and sent into the world to live "useful lives" (thus robbing them of their strange powers) could have read the passages with as much understanding and compassion -- and a subtle trace of anger at the medical establishment's insensitivity in resolving this case.

Sacks is also available reading from Awakenings. This is his vivid account of how some victims of the 1916-27 pandemic of sleeping sickness -- those who survived but suffered a near cessation of thought and movement (though their intelligence and humanity remained intact) -- were returned to the world 50 years later by the drug L-DOPA. What is it like to reawaken in a world no longer your own? Sacks tells these stories with insight, even humor and, as always in his writings, he celebrates the resilience of the human spirit. My sole criticism is that the cassettes, being abridged (the book version of The Man Who Mistook His Wife for a Hat contains 24 case histories, the cassette only four), are much too short. Too bad Sacks didn't read for an unabridged audio version.

Another engrossing cassette set also deals with an awakening -- that of an individual spirit: Alfred Kazin's 1951 autobiography, A Walker in the City. As an essayist, editor and particularly as a critic, Kazin has always suggested that literature must be examined "against the background of man's striving." Here we learn of Kazin's own struggles, as he describes his childhood growing up in the 1920s in the Brownsville section of Brooklyn, a community of immigrant Eastern European Jews.

Walking provides the book's framework and, as Kazin wrote, his meanderings "serve two purposes: to recapture the aliveness of the moment described and to describe walking itself as an exercise in human delight." Kazin seems, in fact, to have walked everywhere in that long gone world of his boyhood -- and remembered all that he saw in photographic detail:

"Beyond Blake Avenue was the pool parlor outside which we waited all through the tense September afternoons of the World Series to hear the latest scores called off the ticker tape -- and where as we waited, banging a ball against the bottom of the wall and drinking water out of empty coke bottles, I breathed the chalk off the cues and listened to the clocks ringing in the fire station across the street."

We walk with Kazin through open air markets, past pushcarts and food stalls and old people sitting on stoops, chatting in Yiddish about the lives they left in Poland and Russia. We walk into synagogues, schools, stores and eventually down streets leading to the "beyond," that strange land outside Brownsville -- the other New York, a world that would eventually call Kazin away to a life rich in music, literature and art. A Walker in the City is more than a mere travelogue or bittersweet recollection, however. It's the recounting of an inner journey, Kazin's search for his American heritage.

Kazin's prose is so compelling and rhythmic that we lose nothing by hearing Michael Prichard read (his narration is fine, but a bit too restrained for the material, I thought) about these sights, aromas, textures and sounds instead of reading them ourselves.

BERYL MARKHAM'S best-selling autobiography, West With the Night is equally arresting, though a world apart from Kazin's Brooklyn. Born in England, she was four years old when her father -- a horsebreeder, farmer and adventurer -- took her to live in East Africa "because it was new, and you could feel the future of it under your feet."

Africa was certainly Markham's future. After growing up on the farm her father wrestled from the raw land, she learned to train and breed racehorses. Then she turned to aviation at 29, flying a small plane filled with mail, passengers and goods to remote sections of Tanganyika, Rhodesia, Kenya and the Sudan. She was an adventurer herself (in 1936 she became the first person to fly solo across the Atlantic from East to West, from England to a crash landing in Nova Scotia), but she was also quite a writer. In 1942 she published this account of her years in Kenya training racehorses, hunting and flying -- at all of which she excelled.

There are two audio versions of her book to choose from, both unabridged, both excellent. One is narrated by Julie Harris, the other by Alexandra O'Karma. Harris is well known for her fine stage and film work, and she's recorded many books on cassette for various publishers. If you're one of her fans, you may prefer her interpretation. But O'Karma, a New York actress, has a distinctive voice -- dark and rich like a fine wine -- that's ideally suited to Markham's elegiac prose.

History buffs may enjoy another unabridged set -- Catherine Drinker Bowen's Miracle at Philadelphia, the story of the Constitutional Convention, May to September 1787. "Miracle at Philadelphia is a narrative," writes Bowen, "taken from . . . contemporary reports of the Federal Convention, from newspapers, diaries, the letters and utterances of delegates and their friends." Here -- as dramatized by Tom Teti (with appropriate musical accents) -- are the voices and thoughts of Washington, Madison, Hamilton, Franklin and dozens of other less well-known men who met in Philadelphia that hot summer to create a new nation out of disparate (and sometimes fractious) states.

Miracle isn't as easy to listen to, however, as it might be to read. Bowen's account is studded with so many facts, figures and players that it's sometimes hard to keep everything straight as it all speeds by on tape -- especially if you're listening while negotiating tricky driving conditions. Such a long and detailed work is best saved for an equally long and relatively unchallenging drive down lightly travelled highways.

IT'S OKAY to laugh while you drive (certainly better than losing your temper), so I'd also recommend listening to archy and mehitabel. These funny and touching poems first appeared in 1916 in Don Marquis' newspaper column "The Sun Dial." They were written, Marquis swore, by archy, a cockroach who lived in the newspaper office and worked by night, pounding these tales out on a manual typewriter. Too light to push down the shift key, archy wrote lower-case free verse, wry and cynical tales of mehitabel (an alley cat whose soul once belonged to Cleopatra) and a legion of urban rats and bugs whose lives and adventures bear a remarkable resemblance to the human condition. Writing about reincarnation, for instance, Archy muses:

transmigration is a great thing

if you do not weaken

personally my ambition is to get

my time as a cockroach shortened for

good behavior and be promoted

to a revenue office

it is not much of a step up but

I am humble

Actor Barry Kraft, who performs these selections has the perfect vocal range and style for the wise and combative archy.

Finally, lest we forget our vacationing children, I recommend Hairyman, a collection of Southern folktales. These aren't readings but lively performances of traditional tales by storyteller David Holt, whom you may have seen on the Grand Ole Opry or the PBS series Folkways. Holt, who accompanies himself on banjo, harmonica, fiddle and guitar, regales his listeners with tales of swamp monsters, strange inventions, witches and magic fiddles.

The publisher, High Windy Audio, also offers three others in the series: Tailybone, scary tales by Holt; and Jay O'Callahan doing animal tales on The Boy Who Loved Frogs and childhood tales on Little Heroes. All are good, clean, traditional American fun, which, after all, is just what you wanted on your vacation. Right?

Vic Sussman writes regularly about recorded books for Book World. WHERE TO BUY AUDIO BOOKS ---------------------------

Book of the Road, 7175 SW 47th St., Suite 202, Miami, Fla. 33155. (305) 667-5762. (Free catalogue.) archy and mehitabel; 2 cassettes, approx. 3 hrs., abridged; $14.95, free shipping with prepaid order.

Books on Tape, Box 7900-P, Newport Beach, Calif. 92658. (800) 626-3333. (Free catalogue.) A Walker in the City. Six one-hr. cassettes; $48 purchase; $12.50 month's rental. Call for shipping charges.

Dercum Pres, Inc. P.O. Box 1425-P, West Chester, Pa. 19380. (215) 647-8799. (Free catalogue.) Miracle at Philadelphia, 12 one-hr. cassettes; $49.95. Call for shipping charges.

High Windy Audio, P.O. Box 553-P, Fairview, N.C. 28730, (704) 628-1728. Hairyman, 44 min.; Tailybone, 39 mins.; The Boy Who Loved Frogs, 49 mins.; Little Heroes, 58 mins.; $8.95 each. Add $1.50 shipping for one cassette, $1 for each additional.

Recorded Books Inc., 6303 Aaron La., Clinton, Md. 20735. 868-786. (Free catalogue.) Sells and rents. West With the Night (Alexandria O'Karma); 7 cassettes, 10 hrs., 30 mins.; $39.95 or $12.95 month's rental.

Spoken Arts Audio, P.O. Box 289-P, New Rochelle, N.Y. 10802. (914) 636-5482. (Free catalogue.) The Man who Mistook His Wife for a Hat; Awakenings. Abridged, one cassette sets approx. 80 mins. each; $9.95 per cassette. West With the Night (Julie Harris), 6-cassette set, 9 hrs., 30 min.; $49. One to three cassette sets, add $2 shipping.