Billions fed, millions dead

What's the most important scientific discovery ever made? Newton's law of gravity? Darwin's evolution? Einstein's relativity? None of the above, according to author Thomas Hager. It was, he claims, a breakthrough engineered by two men you have likely never heard of, Fritz Haber and Carl Bosch. Their great discovery? They learned how to make bread -- and war -- from air, enabling mankind to feed billions more people and kill millions more as well.

All living creatures require nitrogen. So do fertilizer and gun powder. At the beginning of the 20th century, most usable nitrogen came in the form of nitrates from South America. This dependence on faraway nitrate mines posed a huge problem for Germany.

In the event of war, Britain could use its superior navy to blockade the country, cutting off the supply of nitrates and leaving it helpless. In his smooth, well-researched book that reads like a fast-paced novel, veteran science writer Thomas Hager tells the fascinating, but tragic, stories of the two men who solved Germany's problem. Today, their invention feeds the world. But the inevitable unintended consequences again raise the question: How much control should society have over major scientific developments?

The obstacle Haber and Bosch had to overcome arose from the peculiar nature of nitrogen. The element is plentiful, making up almost 80 percent of the air. However, it is in the form of an inert, metabolically useless molecule composed of two nitrogen atoms tightly bound together. To form useful molecules (in which the nitrogen is said to be "fixed"), such as ammonia or nitrates, the tenacious nitrogen-nitrogen bond must be broken.

The problem attracted the attention of Haber, an ambitious young German chemist, at the dawn of the 20th century. Though born a Jew, Haber had converted to Christianity. To prove his devotion to country, Hager writes, Haber "became a German superpatriot." Developing a process to fix nitrogen from air would further his own ambitions -- and those of the Fatherland.

Haber attacked the problem head on. He suspected that the right combination of high pressures, high temperatures and an effective catalyst could break the strong nitrogen-nitrogen bond. Haber had no flash of genius, but he was doggedly determined. Compressors wore out, seals popped, reaction vessels exploded as he tried higher and higher pressures. But he kept at it, modifying conditions again and again.

Starts with a trickle

The hard work finally paid off. In March 1909, Haber ran through the lab. "Come down ...," he shouted, "You have to see how the liquid ammonia is running out!" It was quite an accomplishment, but Haber had produced less than a teaspoon of ammonia. The task of turning his laboratory experiment into a commercial operation fell to Carl Bosch, an employee of the giant German chemical company BASF.

Bosch was a hard-driving, liberal-thinking chemist who had a way with machines. He began to refine Haber's experimental conditions. After making thousands of improvements, Bosch developed a commercial process for producing ammonia -- the raw material needed to manufacture fertilizer and gunpowder. The fertilizer would lead to the making of bread; the gunpowder, the making of war.

Haber and Bosch were rewarded generously for their work. Haber became rich and wound up as director of Germany's most prestigious research institute. Bosch became president of his company. Both men won a Nobel Prize. But tragedy accompanied fame and fortune.

Haber's frantic efforts to prove he was a good, patriotic German led him to become the first person to use poison gas in war. Soon afterward, his wife killed herself, most likely because of her despair about her husband's work on chemical warfare.

'Filled with disgust'

But no matter how hard Haber tried to be the perfect German, he could not erase his lineage. To the Nazis who rose to power in the 1930s, he was just another Jew. "Jews are all communists," Adolph Hitler proclaimed as he issued orders to fire all Jews working in government agencies and universities. Haber was devastated. "I was German to an extent that I feel fully only now, and I am filled with incredible disgust," he wrote to a friend. A year later, Fritz Haber -- depressed and lonely -- was dead. His heart simply gave out.

Carl Bosch's life also turned sour. The ultra-efficient Haber-Bosch plants he built provided him a sense of accomplishment. His satisfaction went up in smoke in 1921 when an explosion destroyed much of one facility. Hager recounts the dreary toll: "561 workers dead, 1,700 injured, around 7,000 homeless. ..."

In a memorial service for the dead, Bosch said bitterly that the explosion "made a mockery" of his life's work.

After the accident, Bosch began to drink heavily. He watched the rise of the hated Nazis and foresaw the bleak future awaiting Germany as Hitler pushed the country toward yet another war. "My entire life's work will be destroyed," he told his family, "and I cannot survive that." He died soon afterward.

Like their up-and-down lives, Haber and Bosch left a mixed legacy. Without their process, the Earth's food supply could not support the current population. Two billion more people are alive today than would otherwise be. But the flip side of the story is less rosy.

Nitrogen made by the Haber-Bosch process pollutes our waterways and creates steadily expanding dead zones in the seas. Furthermore, historians believe that munitions made by the Haber-Bosch process prolonged World War I for one or two years. The number of deaths attributed to extending the war is in the millions.

So, was the development of the Haber-Bosch process a plus for humanity? Bosch himself wonders. "I have often asked myself," he said, "whether it would have been better if we had not succeeded." But, he concluded, "these questions are all useless. Progress in science and technology cannot be stopped."