The World in Its Extreme

N O V E M B E R 1 9 9 1

It is the hottest place in the world, and the driest. It is home to thriving commerce and to desperate, hopeless poverty. It is the Sahara, an eternal source of fascination and terror

by William Langewiesche
The online version of this article appears in three parts. Click here to go to part two. Click here to go to part three.
THE Sahara is a desert so vast that no airplane can diminish it. Certainly this one couldn't. I sat behind the pilots in the cockpit of an Air Algeria turboprop lumbering at 18,000 feet across southern Algeria. The airplane was a Dutch-built Fokker 27, a stodgy forty-passenger twin, doing 220 miles an hour; it had come from the capital city, Algiers, on a roundabout three-day run to the oases. Now we were bound for Adrar, an oasis remarkable even here for heat and lack of rain. It was midday, midsummer. Outside the Sahara stretch in naked folds to the horizon, brilliant and utterly still. It was blanketed by a haze of dust, suspended not by winds but by heat. The only sign of people was a trace of smoke rising in the distance. Below us a canyon cut through the downslope of the Hoggar Mountains. To the south lay the Tanezrouft, a plain so barren that drivers in the open desert mistake stones for diesel trucks, and so lonely that, it is said, migrating birds land beside people just for the company.

The captain wore a white shirt with epaulets. He had pasty skin and the look of an experienced pilot -- bored, dissatisfied, underexercised. He flew with sloppy control motions, like someone enduring a machine that he does not like. For him this was a tough assignment. He was from Algiers, which is on the coast, and had not had time to acclimatize. He must have suffered at night in the oasis hotels.

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For me the flight was a luxury. I leaned over the ventilator and enjoyed the coolness, knowing it wouldn't last. We had come to a road called the Trans-Saharan, a faint scar running north-south across the desert. It was a route I had traveled by bus and truck. Maps show it in bold ink, like an established highway, but much of the pavement is broken and unusable. Across the center of the Sahara it dissolves into bands of braided tracks. Drivers get lost, and each year some die of thirst.

"There is nothing out here," the captain complained. He spoke French, which is the second language of the Sahara, after Arabic.

I thought, Nothing here? But this is the Trans-Saharan, the route of dreams, a way across the desert! On earlier trips I had felt every mile of it. I remembered one ride on a truck, in a passenger box thick with heat, bodies, and dust. We laughed when the first bump threw us from the benches; the second bump smashed us agains the ceiling, and suddenly it was no longer funny. For two days we held on, waiting for the pounding to end. That was the worst. Elsewhere in the Sahara I had felt other miles -- by foot, communal taxi, cargo truck, moped, even river steamer. I had come to the Sahara as others might travel to the Himalayas, to see the world in its extreme. There is no other place as hot and dry and empty. There are few places as hostile to life. Yet it is lived in.

The captain was disgusted by the place. He said, "You let a sheet of paper fall and it takes forever to hit the ground. It's the heat." He tried to be polite. He asked me about the condition of the road. He asked me where I had been and where I was going, and why. He knew I was a writer, and also a pilot, and this made him doubly distrustful. Why would a pilot travel so much by ground? And what was there to say about such emptiness? I tried to explain. He seemed worried about me.

I worry too. The problem is not how little there is to say but how much -- not how empty the Sahara is but how complex. Geographers still disagree about the most basic terms. For instance, if "desert" is defined by dryness, should the pluviometric threshold be six inches of rain a year or twice as much? Should "desert" be defined by variability of rainfall? By rates of evaporation? By hours of sunshine? Or should we choose a human standard and define deserts as places we can neither plant nor settle without irrigation?

Underlying these choices is the question of whether isometric lines drawn on a map can ever encompass the real thing. Describe the Sahara? We can't even measure it. Keeping this in mind, here are a few facts:

The Sahara is the world's largest desert, about the size of the United States including Alaska. It fills the northern third of Africa, stretching 3,100 miles from the Atlantic to the Red Sea. In the north it is bounded by the Atlas Mountains and the Mediterranean. In the south it encounters no geographic barrier. There it has expanded into the populated grasslands of the Sahel, uprooting millions of people, throwing them against one another, and spawning wars. Expansion, which is apparently the result of long-term climatic changes, accelerated by overpopulation, overgrazing, and deforestation, is neither uniform nor ineluctable. There are years even now when rainfall and vegetation push the desert back. From north to south the Sahara is at present about 1,200 miles deep.
There are two central mountain ranges. The Hoggar Mountains, of southern Algeria, climb to 9,852 feet, and the Tibesti, of northern Chad, culminate at 11,204 feet, the highest point in the desert. The rest of the Sahara is flat, made up of plateaus and low hills covered mostly by gravel and rock. Only a fifth of it is sand, formed into dune seas known as ergs. One fifth is still a lot of territory. The Libyan erg alone is the size of France.
The Sahara is geologically ancient. Its basement is gently arching granite, dating back five billion years to the beginning of geologic history. As the continents drifted and the global climate shifted, northern Africa became ocean, forest, lake, swamp, desert, and ocean again. A series of inundations over millions of years laid down the sedimentary plains visible today. The rocks hold mineral riches: oil and natural gas in the north, uranium in the south, iron and phosphate in the west. For the desert people, the most important discoveries have been the vast aquifers in the north.
Unlike deserts caused by features of topography, the Sahara is a weather desert, caused by the flow and physics of the atmosphere. Imagine it as a solar-powered air pump. The thermal equator, a line connecting the hottest points on the globe, runs through Africa ten to twenty degrees north of the geographic equator -- in other words, just south of the Sahara. As air is heated along this line, it rises. As it rises, it cools, and forms rainstorms. These storms define the southern limit of the desert. Meanwhile, at the surface the rising air sucks in dense Saharan winds from the north. These winds in turn are replenished by the air directly overhead. Since the sinking air contains virtually no moisture, northern Africa is a desert. The weather is a closed loop, completed far above the surface by southerly winds.
Evaporation rates in the Sahara are the highest in the world. The relative humidity averages 30 percent, and it has been recorded as low as 2.5 percent. If you measure dryness by the net yearly amount of radiant heat at the surface versus the amount of heat that would be necessary to evaporate the annual rainfall -- the so-called dryness ratio -- the excess evaporative power of the Sahara ranges from a factor of ten to infinity. The ratio is high partly because there is so little rain. Most of the Sahara receives less than three inches a yean (New York's annual rainfall is forty-three inches.) Even the wettest areas, along the outer edges, suffer from unreliability: it may rain today and next week, and then not again for years. There are large areas where nothing grows. At the center of the Sahara are 800,000 square miles of hyperarid plateaus, some of which have been practically sterilized by drought. In such places bacteria die quickly, and cadavers, partly mummified, decompose slowly. Think of sundried apricots.
In the open desert the most successful animals are human beings. The most common are mice, ants, and flies. There are also jackals, bats, lizards, vipers, long-legged spiders, and scorpions. Butterflies and birds fly long distances across the worst terrain. Antelopes, mountain sheep, ostriches, and foxes, once widespread, have fallen to the repeating rifle and the all-terrain vehicle. Of the large Saharan mammals only gazelles remain, and they, too, are being hunted into oblivion. Camels do not exist in a wild state. They may roam at large, but they are bred and branded. Camels are valuable, because they endure in the desert almost as well as Toyotas.

OF the twenty passengers aboard the Air Algeria Fokker only one was a woman, and she was veiled. She sat stiffly, not daring to look outside, while her children wandered the aisle. The men seated near her wore white robes and turbans. They were Arabized Berbers and Berberized blacks -- traders, students, soldiers on leave. Some had the beards of the Islamic revival. In the back sat four Tuaregs, lanky, fine-featured nomads of the central Sahara. They smelled of woodsmoke, and wore chËchËs, long cotton strips wrapped around the head and forward across the nose and mouth. The chËchË is more than an answer to sun and dust; it masks the wearer and gives him the power of anonymity. The Tuareg are renowned warriors. They fought off the French into this century. Now, across the Tanezrouft, in Mali and Niger they have risen again in rebellion against the central governments.

The Tuareg are Berbers too, like most people in the Sahara. "Berber" is a broad descriptive term that includes a wide range of groups descended from Eurasian horsemen who arrived 3,000 years ago. It derives from barbarus, Latin for "foreign and uncivilized," and, unintentionally, it still expresses a common attitude toward North Africans. Saharans are also called Arabs, which might be a more polite label. The Arabs are if anything overcivilized. Their armies came to the northern Sahara in the seventh century A.D. Though the armies didn't stay long, Arabs interbred with the Berbers, and imported a language, a culture, and a new religion -- Islam. Over the following centuries this potent Arab combination spread south, gradually weakening and replacing the Berber traditions. Today, although there may yet exist in the Sahara some "pure" Arabs, and there are a good many pure Berbers, the majority of the Sahara's population represents a mixture to some degree.

The Sahara is an Islamic desert, but this does not mean that it is a unified desert. Throughout the Sahara you hear the refrain "Our Islam is the true Islam," implying that the neighbors' is not. The neighborhood consists of ten sometimes unfriendly nations. Recent events in the Persian Gulf have heightened their differences. As you might suspect by looking at a map, the borders between them are arbitrary. They were drawn to meet the needs of colonial administration, and they remain wild and unmarked. Nonetheless, when you cross one, what is surprising is not how little the desert changes but how much the context does.

In the south are four landlocked countries -- Mali, Niger, Chad, and Sudan. These are miserable places, bearing the brunt of the desert's expansion and plagued by civil wars. Along the coastline are the five countries of the Mahgreb: Mauritania, Morocco, Algeria, Tunisia, and Libya. None is happy. Mauritania is brutal and xenophobic; Morocco suffers under a reactionary king; Algeria and Tunisia are politically and economically bankrupt; Libya, the only wholly Saharan nation, has been cursed with Muammar Qaddafi. Egypt, to the east, along the Nile, is a riverine society with problems too intricate and particular to summarize here.

Throughout the Sahara a sense of change is in the air. Socialism, liberalism, and military rule have failed. Pan-Arabism has proved to be an empty promise. But over the past few years a potent ideology has resurfaced -- Islamic fundamentalism. Islam is a religion that provides for both law and government. Ever since the Iranian revolution it has taken on new relevance, as an alternative to the models of the West, as a homegrown answer to disorder, corruption, and inequality. The large, vigorous fundamentalist movement has become the dominant political factor in the Sahara.

North African fundamentalists are Sunni Muslims, less frantic than the Shiites of Lebanon and Iran. No one knows what will result if they take over. Will there be more Irans -- radical, repressive, and hostile to the West? Or will something new and more benign be created? In Algeria the Islamic party may eventually seize power. An Islamic government there would have profound -- perhaps revolutionary -- effects on the entire region.

Water in Adrar

Adrar is a provincial capital in central Algeria, a town of 15,000, laid out in wide streets between ocher buildings. It sits at the center of a region of oases known as the Touat, astride an ancient caravan route from Gao and Timbuktu. I went there to look at irrigation. My host was a young merchant, Moulay Lakhdar Miloud. Moulay is a title of respect. There are a lot of Moulays, and many seem to know one another. I once heard the Sahara described as the United States of Moulay.

Moulay Miloud is a bachelor with a narrow, intelligent face and a moustache. His friends call him Uncle Moulay. He was dressed in a pressed white robe. We sat on the floor of his living room and waited out the hot midday hours, drinking brown water from a plastic jug. The water was brown because Miloud had mixed in cade oil. The cade is an evergreen bush that grows in the Atlas Mountains. Saharan nomads use its oil to seal the inside of goatskin water bags. Miloud did not have a goatskin, but he came from a long line of desert travelers. He bought the oil in small bottles and added it to his water for flavor and good health. The mixture smelled of pine sap and tasted of clay. Miloud smiled, pleased that I liked it. But I would have drunk anything. I had been for a walk.

"It's raining less," Miloud said. "And every year it's hotter. Nomads can no longer survive this climate. "

I believed him.

The house, like Miloud, was small and immaculate. It had a fan and an evaporative cooler. The living room was furnished Saharan style, with mattresses, pillows, and colorful rugs. Black-and-white enlargements of nomads hung on the stucco walls. A guitar stood in the corner. The Cosby Show, which is broadcast by national television, flickered soundlessly on a TV screen. A stereo played screechy Saharan music. In the hallway, by a portrait of Bob Marley, was a postcard of three naked women. They were grotesquely fat. Miloud said, "In the summer even the mind shuts down. You get tired of television, music, and books. There is no stimulation. There is little to say. You are too much indoors."

For good reason. Outdoors the temperature was 124 degrees Fahrenheit. During my walk the air had been still, the sky milky with dust. There was no shade. The streets were deserted. The heat hit hard, a physical assault, burning skin, eyes, and lungs. I felt threatened and disoriented. I had drunk my fill beforehand, but an hour without water was all I could stand.

The Sahara is hot because it is sunny. In Adrar out of some 4,400 hours of annual daylight there are 3,978 hours of direct sun, on average. (Paris, home of the great Saharan colonizers, gets 1,728 hours of sun.) Elsewhere in the desert the count is equally high. And this is steep-angle sunlight, powerful stuff. In the winter, air temperatures can drop to freezing at night and rise to 90 degrees by noon; soil temperatures can fluctuate so brutally that rocks split, a process called insolation weathering. In the summer the Sahara is the hottest place on earth. The record, 136 degrees. Fahrenheit, is held by al Azizia, Libya. Airborne dust makes things worse. It traps heat radiated by the hot soil, and is why in Adrar the desert does not cool much on summer nights.

Late in the afternoon Miloud and I drove an old Renault to one of the outlying oases. The road was paved. It led past neglected palm groves and then across rolling sand and dirt. In the far distance I could make out the dunes of the Erg Chech, the enormous and uninhabited sand sea that extends 600 miles, across Mali and into Mauritania. Miloud said, of the land on either side of the road, "In the winter all this is green." Translation: if it rains, a few translucent grasses may sprout. The average annual rainfall in Adrar is less than an inch.

The two dozen oases of the Touat sit at the receiving end of the largest dry watercourse in the Sahara, an ancient riverbed called the Messaoud. It is a long, shallow depression where water still lies close underground. Oases are not the waterholes of public imagination but irrigated groves of date palms. They are artificial creations. The ones in the Touat are famous for the engineering of their traditional wells. Known as foggaras, these are gently sloping tunnels, burrowed for miles into higher terrain. Since their paths are marked by frequent mounds around excavation shafts, they look like the diggings of giant moles. The foggaras were built centuries ago, not to find water but to bring it to the oases in a constant flow. They are self-filling subterranean aqueducts. They are not, however, self-maintaining.

Our destination appeared as a green line against the dusty sky. The line became a palm grove and an ancient fortified village, or tsar, of about a thousand people. In searing heat we walked through the streets -- a warren of baked mud and dark, built-over passages just wide enough for a loaded camel to pass. There were no camels now, only a few sad donkeys hauling firewood. The inhabitants were Haratin blacks, descendants of slaves, who still occupy the lowest level of Saharan society. Racism exists throughout the desert, though it is tempered somewhat by the egalitarian precepts of Islam. I do not mean to suggest that modern Islam has brought enlightenment to the Sahara. Fundamentalism never seems to promote understanding. But Saharan society is noticeably different from ours in the way it is softened by the vitality ot its religion.

A band of dusty children followed us into the desert to the foggaras. Water was still flowing, but the foggaras were slipping into disrepair. One reason is that maintaining them -- digging them out, shoring them up -- is dangerous and difficult work, and since the abolition of slavery there has been no ready supply of labor. A more immediate reason was in the concrete shelter nearby. It housed an electric pump, drawing water from a bored well. The modern world had arrived, and no one was complaining.

The system of distribution was still the traditional one. We followed the ditches that carried the water back to the village. Upstream it was drawn for drinking; downstream it was used for washing and sewage. The water that finally flowed toward the palm grove was, let's say, rich in nutrients. It was also precious. Water rights are inherited, bought, and sold, and are more valuable than the land itself. Within the grove the water is divided and metered through finger-width gateways into an intricate branching of channels. In the end it spreads into individual plots, separated by dikes and protected against wind and sand by adobe walls. There the date palms grow.

Date palms are well adapted to the Sahara. They thrive on sun and heat, and will produce fruit in water that is ten times as salty as human beings should drink. Though they require large amounts of irrigation for the first few years, they then tap into groundwater and become self-supporting. They also shade the irrigated vegetable crops -- most commonly corn and tomatoes.

This grove was small by Algerian standards -- about a half square mile of junglelike vegetation. We strolled through it on dirt paths between the plots. The shade was dense, but it provided no relief from the heat. Dead fronds drooped from the trees and littered the ground. Miloud pointed to them and said that when he was young, the farmers would have been ashamed. Yellow butterflies flitted about. Ants carried oversized trophies. A turbaned man hacked at the earth. A ditch gurgled with polluted water. I stopped to list the other sounds: the distant music of Arab horns, a dove cooing, a donkey braying, a cricket, birds trilling, children laughing, the thunk of a woodchopper, a sharper hammering, a rooster crowing, flies buzzing, a chanted prayer.

EARLY one morning Miloud and I drank coffee at a cafe. The conversation turned, as it often does with young Saharans, to religion. I listened and tried to understand. But when Miloud mentioned his hatred for Jews, I answered back. I said that he was mythologizing them. I said that even if, as an Arab, he resented Israel, he had to distinguish Jews from Israel. I said that he even had to distinguish Israelis from one another. He retreated to history and talked of what he called ancient crimes -- the Jews' unwillingness to accept the new word of God and his Prophet. Muslims have a strictly chronological view of progress: their faith rests in the idea that Mohammed was the final prophet, and that his message supersedes all others. I asked Miloud how he could hold individuals responsible today for the deeds of their distant ancestors. I said, What if I were a Jew? He answered, But you are not. He was unbending, and our arguments became circular.

I remembered a conversation with a policeman in another oasis. He said, "The French? Oh, yes, we fought a war; we hate them."

I asked, "What about the Russians?" The oasis had a military base and a small contingent of Soviet advisers.

"They are godless. We hate them, too."

"And the Germans?"

"They are fascists. We hate them."

"And Americans?"

"Oh, no, Algerians do not hate Americans." He hesitated. "Except for imperialists and Jews -- we hate them most of all."

Since there are few Jews remaining in the Sahara, the anti-Semitism there has become somewhat academic. It is disquieting nonetheless. I have friends in the northern Sahara whose daughter is a bright, charming schoolgirl, a picture of sweet innocence. Once when I was over for dinner, she smiled and said, "If an Israeli ever came here, I would . . ."

"What would you do?" her mother asked gently.

"I would kill him."

The television news had been filled with brutal home videos of the Intifada, the Palestinian uprising. They have become a staple of Islamic solidarity.

THERE is a limit to the insulating qualities of adobe construction, a temperature extreme beyond which walls go critical and begin to magnify the heat. I have studied this: the walls do not cool down at night; at dawn the inside surfaces are hot to the touch; by day they are hotter still. The houses become solar ovens. Concrete is worse: it gets hotter in sunlight and no less hot after dark. In the big Soviet-style buildings you can burn bare feet on the second floor. Air-conditioners and evaporative coolers are rare, and replacement parts are rarer.

During the peak months of summer people move outdoors. In the morning and late afternoon they sit in the shade cast by the walls. At midday they hide as best they can, under an awning or a tree. Strangers flock to the hotels, where the lobbies have fans and high ceilings. The secret police flock there too, for the same reasons, and also to investigate the strangers. Everyone waits. At night, while hotel guests lie trapped in their rooms, the Saharans eat and sleep in the gardens.

Miloud and I went to dinner in Adrar at the house of Nouari, a bookish construction engineer. He had also invited a tall, shy hydrologist, who the next day was to guide me through a modern irrigated farm north of town. The four of us sat on carpets in the sand behind the house.

It was a sweltering night, the temperature still over 100 degrees The stars were blackened by dust. The meal was lit by kerosene lanterns on a barrel. Nouari's wife and mother cooked for us but did not appear. Sexual apartheid reigns in much of the Sahara, and pudency demands that women stay hidden from male guests. I made no mention of the women. Nouari poured water from a pitcher and we washed our hands.

We started with raw milk and dates. Nouari said, "The Prophet recommended dates."

Miloud added, "Milk and dates make a complete meal. They are all a person needs to eat."

Nonetheless, we also had tripe, couscous, and melon. Afterward we drank tea brewed by Nouari on a butane burner, and the discussion returned to dates.

Dates are so important that oases are measured by the size of their groves. The largest have more than a million trees; the smallest have a thousand. After the Algerian war of independence against the French, which ended in 1962, the groves were nationalized by the socialist regime. Later they were privatized, returned to the original owners, but they have not recovered their earlier glory. The inhabitants of the oases are crazy about their dates. They eat them directly off the branch; they dry them and eat them; they bake, boil, and fry them and eat them. They are date gourmets, and can distinguish hundreds of varieties by taste, texture, and color. They know date facts: that a thousand dates grow in a single cluster, that half the weight of a dried date is sugar, and that dates are rich in minerals and vitamins. Nouari listed them, taking care that I note every one: "Vitamins A, B, C, D, E."

The hydrologist added, "Dates help against cancer. Research is being done in the United States at a big university."

Nouari described the yearly pollination performed by the farmers. He recited the line from the Koran that is read while this is done: "In the name of God, mild and merciful. "

Miloud observed that the tree itself is a wonderful resource. With help from the others, he went through all the uses of it. They are too many to list here, but they can be summarized as follows: things that can be done with wood and palm fronds. The hydrologist finished by saying, "The Prophet loved the tree too." It is not surprising that the neglect of the groves in the Sahara has added fuel to the fire of Islamic revolt.

THE hydrologist's name was Sollah. In the morning he took me to see the irrigated farm, which he called a model. It sprawled across 800 unshaded acres in virgin desert -- an American-style operation, privately owned, with a bright tractor and a crew of Haratin black workers. Circular irrigation systems stood over wheat stubble. There were greenhouses, and plots of tomatoes, peppers, pimientos, cucumbers, melons, and cantaloupes. There was plenty of mud. This was modern agriculture -- energetic, productive, and perhaps wasteful. I told Sollah that it looked like farms in California. He was pleased, and asked why. I answered, Cheap water. This pleased him even more, because it was his water. He had directed the government crew that drilled the first well.

We went to drink the results. Two pumps drove a heavy flow of water into a holding tank. The water was sweet and cool. They had struck it with an Oklahoman rig at a depth of 450 feet. The water ran dirty with sand and mud for two days, and afterward turned clear. The project took a month to complete, which is about average. There are several crews like Sollah's in the province. Together they have been drilling forty-five wells a year. Every well has produced.

Most of the Sahara is too dry for drilling. If you do hit water, either there is too little or it is too salty or too expensive to pump out. It might sustain a few settlers, or people passing through. It is not worth thc cost of getting to it. But here, in the northern third of the desert, large reserves of fresh water lie under the parched surface. The shallowest have for centuries irrigated the towns and oases. They can be got at by foggaras and hand-dug wells. They are susceptible to drought and overuse; the water table falls, crops fail, and settlements must be abandoned. But if it rains, even far away, eventually the shallow reserves are replenished.

Of greater importance for the future are the deep aquifers, whose discovery was a by-product of the search for oil. The mere knowledge of their existence has had a profound effect on life in the Sahara. Known as confined aquifers, they are pools of fresh water trapped in permeable rock strata at depths of 300 to 6,000 feet. They hold as much water, according to one estimate, as the Amazon River discharges in two years. That is a lot of water. What's better, much of it is under pressure. Once tapped, it rises to the surface and forms artesian wells. Geysers have shot hundreds of feet into the air. Wells have been capped to keep villages from flooding.

Water works powerfully on the souls of Saharans. Muammar Qaddafi has launched an agricultural revolution in Libya, and is building gigantic irrigation projects. He believes he will transform his sands. If for nothing else, he is respected for this. Other Saharans have equally grandiose dreams. Miles of tomatoes, potatoes, rice paddies, fish farms, horizons of grain -- the United States of Moulay. If there is water in the desert, anything is possible. Sollah, a quiet and rational man, was suffused with the glory of his mission. Even the taxi driver who took us out to the farm had an opinion. He believed that irrigation would eventually bring rain. Call it reverse desertification, the trickle-up theory.

But there is a problem. The deep aquifers are being recharged very slowly, if at all. This means that the aquifers contain mostly fossil water, deposited long ago, when the Sahara was not a desert. The water that Sollah and I were drinking was perhaps 5,000 years old. In western Egypt well water may be five or ten times as old. My comparison to California was only partly correct. Much of the irrigation water in the American desert comas from rivers and reservoirs -- short-term, renewable surface supplies. Some waste is perhaps affordable. The deep water of the Sahara is different: you pump it here for keeps. Like oil, it is not renewable.

A second problem is that despite the large reserves, only a small fraction of the stored water can be extracted economically. There are many reasons for this, including lowering tables, loss of artesian pressure, expense of drilling, expense of pumping, and increasing salinity. Scientists argue that new wells should be drilled sparingly, and water used wisely. They use terms like "practical sustained yield" -- meaning you take out no more than is going in. They say an aquifer is like a bank account -- if you must draw it down, the reason should be to build a return in the long run. They warn about unchecked exploitation, and talk about the end's coming as soon as 2025.

Their advice passes like wind. Saharans are no wiser than the rest of us. They dream of green. It is the color of Islam. In Algeria the fundamentalists have promised to make a garden of the desert. Words come easily.

The online version of this article appears in three parts. Click here to go to part two. Click here to go to part three.