Continental Drift : The questing journey of five people : THE STONE RAFT, <i> By Jose Saramago</i> . <i> Translated from Portuguese by Giovanni Pontiero (Harcourt Brace: $23; 292 pp.)</i>

At the start of “The Stone Raft,” a river that flows from France into Spain disappears into the ground. Soon a rift appears, bisecting the Pyrenees lengthwise; in a day or two the rift is 30 feet wide. The entire Iberian Peninsula has broken off from Europe and begun to head west across the Atlantic; slowly, at first, and then at a rate of some 30 miles a day.

By the end of the book, Spain and Portugal, the great stone raft of the title, will have made a jog north to avoid decapitating the Azores, will head for North America, will stop and slowly revolve so that Lisbon faces east and Barcelona west, and then slide south to come to rest partway between Central America and Africa.

Hundreds of thousands of Spaniards and Portuguese take to the road to explore a world that is suddenly finite and utterly changed. Tourists flee and so do investors. The European Community protests the departure of an Iberia it had been reluctant to admit in the first place. NATO makes a fuzzy pronouncement, its approval indistinguishable from its disapproval. The English are delighted when Gibraltar snaps off from the end of the moving peninsula and remains in the middle of the sea, solitary but entirely the queen’s. Young people all over Europe clash bloodily with the police under the slogan: “We are all Iberians now.”

Ruptures, new beginnings, the shaking-up and turning upside down of the ingrained miseries and dead--ends of contemporary life. If Jose Saramago, Portugal’s great fabulist, were simply attempting an ironic political and social allegory, all these things would fit in neatly. “The Stone Raft,” which may be Saramago’s finest work--he also wrote “Baltasar and Blimunda” and “The Year of the Death of Ricardo Reis”--is much more than that.

It is the questing journey of five people who come together from five different parts of their questing peninsula: their land voyage set atop an ocean voyage. When the bank clerk Sassa from Oporto meets the schoolteacher Anaico in his village in the Alentejo, they are the first two to join together. They lie out all night under a moonlight that has never before bathed these particular olive trees--now 70 miles and several days west of themselves. From this particular angle, they ruminate. Anaico recalls that Portugal’s great King Joao~ II once bestowed an imaginary island on a courtier, who then set out to find it. “This other island,” Anaico says, “the Iberian one, which was once a peninsula but is no longer, I find just as amusing, as if it had set out to sea in search of imaginary men.”

The wandering of Saramago’s Spain and Portugal is more than a geological outrage. It is as if one large chunk of the earth, sick of or feeling sorry for its becalmed and deadened humanity, had decided to get the human faculties of imagination, generosity and discovery moving again--by moving itself. Saramago’s lovely and original questing story, in a lineage of such others as “Don Quixote” and Kipling’s “Kim,” is a journey of the spirit told as a journey of the feet.

To have five people trudge on a pilgrimage through a contemporary Western panorama could be forced and artificial, as Kerouac’s “On the Road” partly was. With Spain and Portugal mysteriously pirouetting around the Atlantic, a supercharged end-of-time condition is evoked--doomsday and resurrection at once--and it allows Saramago’s characters to undergo a metaphysical adventure while performing in a register that is natural and entirely winning.

Each is utterly his or her cranky and curious self; each touches at some point the supernatural phenomenon that sends Iberia gadding about. At the same moment that the rift in the Pyrenees appears, the following has just taken place:

Sassa, strolling on the beach near Oporto, idly picks up a 13-pound stone and heaves it into the water. Instead of plopping, it soars, comes down on the water, skips up again and keeps on skipping until it reaches the horizon. Anaico, walking near his village, is suddenly joined by a host of starlings that follow him wherever he goes.

Pedro Orce, a small-town Spanish pharmacist, stamps his foot and from that moment on, the ground never stops shaking beneath him. Guided by television and newspaper reports of these phenomena, Sassa seeks the other two out. They set off in Sassa’s tiny car: first, to the Malaga coast to see Gibraltar passing (or rather, Spain passing Gibraltar), and then to the Atlantic.

The cloud of starlings on their Lisbon hotel roof guides Joana Carda to them. She had left her husband and their home in Coimbra and retreated to a village to consider her life. At the moment of the Pyrenees crack she had drawn a line in the dirt with an elm branch: herself on one side, Coimbra on the other. However persistently it is scraped or dug over, the line cannot be effaced.

She and the three men go to inspect it. A mastiff appears with a bit of blue thread in his mouth. By various canine signals (“Man proposes, dog disposes”), the mastiff leads the tiny crowded car through Portugal and up to a farm on the northern Spanish coast. Maria Guavaira, who lives there, had been unraveling a blue sock at the moment the rift opened. The mastiff had appeared at her door, bit off a length of thread, headed south and returned with the others.

The five repair a wagon and set out through northern Spain, buying and selling clothes to support themselves, visiting the Pyrenees--which now end in a one-mile sheer drop to the ocean--and heading south. Anaico and Joana pair off; so do Sassa and Maria. Orce, old and lonely, has the mastiff as companion and once each--out of sexual bountifulness--Joana and Maria. There are jealousies as a result, and reconciliations; above all there is the sense of five innocents, their slates wiped clean by the voyage of their stone raft, trying to figure out how to draw a human being. It looks much as a human being has always looked, in fact. The magic evoked in Saramago’s book is in the opportunity to draw once more.

He writes in great balloon-like sentences. A sentence may include two or three different characters speaking, a bit of narrative or description, a comment by the author, a digression on the comment. Greek protagonist and Greek chorus are rolled into one. Things flow together, separate, join. Here, for example, is Sassa setting out on a walk; soon it is the author walking:

“He was one of those travelers who go neither in debt nor in fear, he set out early to enjoy the fresh morning air and to make the most of the day, tourists who are out and about early are like this, at heart troubled and restless, unable to accept life’s inescapable brevity, late to bed and early to rise does not make one healthy, but it does prolong life.”

Saramago’s balloons need time and patience, particularly at first. Bit by bit we do not simply get used to them; we find in them--skillfully translated by Giovanni Pontiero--the essence of his humane and magical art. They fill with words, they take on assorted cargo, they lurch up, and soon we are moving giddily over a panorama of the world infinitely stretched out below.