Postcards from America, the newly published book by a group of five Magnum photographers and writer Ginger Strand, recounts a two-week road trip through the American Southwest in May 2011. Here, published online for the first time, is “Treasure: A True Story,” a collaborative project from the book featuring Strand’s writing and photos by Minnesota’s Alec Soth.

I. Lost

This is the story: long ago, Jesuit Padres found a rich vein of gold in the mountains north of El Paso. They mined it for years. But then something happened—an Indian charge, a detachment sent to collect taxes for the Crown—and the padres decided to hide their mine. They put all their tools and valuables inside and sealed the entrance with red river mud. Then they disappeared, and the mine was lost.

Since then, many people have gone looking for the mine, but it doesn’t want to be found. A Mexican vaquero brought home a gold brick he found there, but he was promptly struck blind. A pair of woodcutters saw a rattlesnake dusted with gold, but when one of them went to get their digging tools the other was swallowed by a landslide. Residents of the Tularosa Valley say the mine is guarded by a shape-shifting witch who chases treasure-hunters away. In the 1890s, a prominent lawyer from Mesilla, New Mexico, went to Lincoln to prosecute some cattle rustlers. As he and his 8-year-old son journeyed home through the Tularosa Valley, they disappeared. It was rumored they were killed by the cattle rustlers. It was rumored they were killed by a rival lawyer. But some people said they were killed by the curse of the Lost Padre Mine. Their bodies have never been found. The lawyer’s name was Albert Jennings Fountain.

We want to find the Lost Padre Mine. We at least want to understand the story. We think Albert Fountain’s descendants might point us in the right direction.

II. Bolson

Arlene Fountain has moved. Armida Fountain is not home. Christina Fountain does not pick up. David Fountain, David E. Fountain and Larry Fountain have all changed their numbers. Leon Fountain and Marcia Fountain do not answer. Maria Fountain comes to the phone. We meet her at the Tax Appraisal District offices, where she is going to protest a charge.

Maria Fountain hasn’t heard of Albert Fountain. She doesn’t think her husband is related to the prominent Fountains, because he’s from Georgia. They met in the Army and moved to El Paso. She would like to move out to the country. “I love the animals and the trees,” she tells us. “There are so many water restrictions in El Paso. But sometimes my plants call me and I can’t fail them.”

In El Paso, you are only supposed to water on certain days determined by your house number. El Paso gets most of its water from the Hueco Bolson. A bolson, from the Spanish word for purse, is a large, saucer-shaped basin that collects water, the way the bottom of a woman’s purse collects coins. We look at a map. The Hueco Bolson lies beneath the Tularosa Valley, the place where Albert Fountain disappeared.

In 1958, another local lawyer wrote an article warning that water was being pumped out of the area’s bolsons faster than the aquifer could recharge. “Here the supply is being ‘mined’ under a calculated plan of depletion,” he wrote, “over a period of sixty or seventy years.”

III. Oryx

The area is running out of water now. El Paso built a desalination plant in the 1990s. Experts said it would be cheaper and easier to recycle water, but people don’t like the idea of drinking their own pee. Only astronauts have to do that. A city in the desert is like a space station, but people don’t like to think so. The El Paso Water Utility calls the desalination plant “a critical component of the region’s water portfolio.” In the desert, water is money in the bank.

Art, the plant supervisor, shows us around. On the control room wall is a large photograph of an oryx. The oryx is standing by one of the injection sites where the salty concentrate separated from the bolson’s brackish groundwater is pumped into deep wells. Four thousand feet down, Art tells us, the concentrate joins warm water that’s already saltier than the ocean. We imagine swimming down there, buoyant and warm and blind.

Water law divides water into groundwater and surface water but hydrologists say this is silly. Hydrologists say that no water belongs to ground or surface; all water is simply molecules endlessly moving between sky, ground, ocean and sky again.

Art gives us conical cups of desalinated water to drink. When it is stripped of salts and minerals, he tells us, the water gets aggressive. They blend it with fresh well water to calm it down.

We don’t ask about the oryx.

We don’t ask why an African antelope is guarding the spot where El Paso deposits the minerals stripped from its water back into the earth’s dark bank.

One thing we know is true of oryxes: they can go for weeks without water.

IV. Joel

We tell our driver, Joel, that we want to go to New Mexico and find the Lost Padre Mine. We tell him we have a feeling it’s in the San Augustin Pass, in the Organ Mountains, not far from where Albert Fountain died.

Joel knows about the Fountain family. He tells us a story. In middle school, in science class, he made a rocket. The whole class took their rockets outside to set them off. Joel’s worked beautifully. It launched in a fountain of sparks into the blue New Mexico sky. It came back down and landed in a leafy oasis across the street. Joel wanted to go get his rocket, but the others wouldn’t let him. That’s the Fountain house, they said. You’re not allowed on the property.

Albert Fountain, Joel says, died a wealthy man. He owned a theater in downtown Mesilla called the Fountain Theater. He also owned a watering hole called El Patio. His grandson owns the place today. Joel takes us there. Everyone inside is complaining that the cat has peed in the air conditioner. But no one leaves. We drink beer. The bartender calls the Fountain grandson for us but he didn’t pick up. There’s a picture of him behind the bar, flanked by two girls in tight t-shirts.

Wealth is slippery. We try to control its circulation, but it dries up, floods the market, trickles down, turns out to be a mirage. It can hold you afloat. It can drown you. At the Fountain house, Joel’s rocket sleeps in its tree. We aren’t allowed on the property, but we go. There’s a fountain in the circular driveway. The rocket is nowhere to be found. It doesn’t matter. The rocket is not the thing. The rocket is the lift-off, the buoyant ascent, the parabola inscribed on the New Mexico sky, the glide back down into the eager Fountain trees.

V. Found

In the San Augustin pass, we park at a gate that says “No Trespassing” and squeeze through a barbed wire fence. We are on the White Sands Missile Range. We start up the mountain, looking for the mine entrance. Up ahead, we see an animal standing still. At first we think it’s a burro. Then we think it’s a cow.

No, Joel says, it’s an oryx. I’ve always wanted to see one. To me they’re like unicorns or something. Which is funny, because this oryx has only one horn.

The oryx stands very still. We talk to it in soft voices, to calm it down. We don’t want to scare it. We split up and move closer. It looks slowly from one of us to the other. It isn’t scared. It drops its head once, slowly, like a courtier or a Japanese businessman. We don’t realize what this means until it charges.