The Alchemy of Air: A Jewish Genius, a Doomed Tycoon, and the Scientific Discovery That Fed the World but Fueled the Rise of Hitler

by Thomas Hager

Homer sang of farmers gathering heaps of mule and cow dung. The Romans worshipped a god of manure, Stercutius. Rome made an early science of agriculture, ranking various animal excrements (including human), composts, blood, and ashes according to their fertilizing power.

In the most intensively cultivated land in Europe—the Marais district of Paris—owners of small city-garden plots applied dung at rates as high as hundreds of tons per acre, and every year they had to repeat the process. By 1700 or so, hungry Europeans were experimenting with other soil additives in an attempt to increase their yields, trying sea salt, powdered limestone, burned bones, rotting fish, anything that might keep their soils producing.

China, farmers a millennium ago were already expert in using every possible kind of fertilizer, hoarding their human waste and adding it to the output from their domestic animals, composting vegetable scraps and leaves, and tossing in seed cakes to enrich their fields. It was all applied to the most ingenious farm system imaginable: a complex of dike-and-pond fields in which they grew not only rice, mulberries, sugarcane, and fruits but also carp. The fish waste helped fertilize the crops. The dung of the water buffaloes used to work the fields helped fertilize the crops. So did the waste of the ducks that swam in the ponds. They grew a native water fern in the paddies that acted like a crop of soybeans, adding fertility to the soil. The tropical climate allowed multiple harvests per year. This was the highest-yield traditional agricultural system ever devised. Using it, the Chinese could feed as many as ten people with the output from each acre of farmland, a yield of food five to ten times higher than the European

the creation of vast amounts of fertilizer, new fertilizer by the thousands of tons. As there was not enough natural fertilizer in the world to meet the needs of the coming twentieth century, some way would have to be found to make more, to make it synthetically, to make it in factories. Finding new ways to make fertilizer, discovering and making what he called chemical manures, Crookes told his audience, was the great challenge of their time.

In the hundred-plus years since Crookes gave his speech, the human population has doubled, and doubled again, and will double again in the next few decades. As a species we long ago passed the natural ability of the planet to support us with food. Even using the best organic farming practices available, even cutting back our diets to minimal, vegetarian levels, only about four billion of us could live on what the earth and traditional farming supply. Yet we now number more than six billion, and growing, and around the world we are eating more calories on average than people did in Crookes’s day.

The goal of alchemy was to distill the pure soul of nature from the rough, chaotic stuff of the earth, to find the spirit hidden in matter. God was in everything, even the rocks, and alchemists believed their work was a way to understand the workings of the divine. They

These were the Chinchas Islands, a sprinkling of rocks six miles off the coast of Pisco, Peru, which constituted, in 1850, acre for acre, the most valuable real estate on earth. The value came from the ground the workers and the birds walked on: ten stories of guano, the world’s best fertilizer. The ground everywhere was springy to the step.

Peru, home of almost all the easy wealth, the gold and silver of the Incas, had as a result received most of the attention from Spain. The Spanish conquistadores had turned it into a vassal nation, raped it, and looted its riches. It became even after independence a nation of a few very rich families ruling many extremely poor citizens. Chile, by comparison, had many fewer Indians, far less natural wealth, and a heavier influence of settlement by German and British immigrants. The Peruvian tradition was one of aristocratic control, slave labor, and resource exploitation. The Chilean tradition was relatively progressive, nationalistic, enterprising, and aggressive. The Chilean government was stable. Chileans were compared by some historians to the American pioneers.

N2 is held together with a triple bond, the strongest chemical bond in nature. Breaking it and freeing the individual N atoms requires enormous amounts of energy, heat on the order of 1,000°C, intense enough to to melt copper. The only thing in nature hot enough to break apart N2 is a bolt of lightning.

Finally, questions remain about how the flood of Haber-Bosch nitrogen is affecting human agriculture and global populations. The easy availability of synthetic fertilizer has resulted in an increase in massive-scale monoculture farming, with the additional corn and other grains making possible huge animal factories. Haber-Bosch is not the only reason for our current agricultural system—increasing mechanization and advances in plant genetics are important as well—but it plays a major role. Most humans have moved past the old traditional methods of crop rotation and manuring, severed the old ties between crops and domestic animals, increased average farm sizes and decreased crop varieties. These developments offer terrific benefits, feeding many more people much better than our ancestors thought possible—but they also carry clear risks for soil quality, plant disease, and decreased diversity. EVERY SCIENTIFIC DISCOVERY is two-edged. We have been so successful at meeting Sir William Crookes’s challenge that humans now threaten to overrun the earth, just as nitrogen-eating algae and water plants overrun ponds and seas. Thanks to our recent access to endless fertilizer and the development of hardy, high-yield varieties of rice and wheat (the so-called Green Revolution of the late twentieth century) we are confronted with an abundance of food unprecedented in human history. Thomas Malthus has been confounded. Ours is an age marked not by mass starvation but by the easy availabil...