The Salt of the Earth - Ocean Worlds: The Story of Seas on Earth and Other Planets - page 68

6 milligrams in every tonne of seawater: not a large amount, but not
trivial either if a means could be found of extracting it.
Enter, two decades later, Fritz Haber—another giant of chemistry,
and indeed another Nobel Prize winner. Haber is a man who, literally,
allowed humanity to grow. He invented an effective means to turn
nitrogen from the air—a very unreactive gas—into ammonia, the
feedstock for nitrogen-based fertilizers. About half the protein in
your body (and in ours, too) is built around nitrogen fixed by the
Haber process. Without it, half the world would starve. With it, there
will naturally be consequences, which we will explore. But for now
we can simply turn to one of the more curious episodes in the life of
Haber, a man whose life combined high achievement and deep trag-
edy. 48 In 1920 he was a famous German scientist in a Germany crushed
under the weight of Allied demands following the end of the First
World War: a total of 132 billion gold marks had been demanded as
war reparations.
Haber wanted to save his country from penury, and remembered
Arrhenius's work on gold. He repeated Arrhenius's analyses and came
up with similar figures. A golden future beckoned. With colleagues,
sworn to secrecy, he set sail on the oceans to follow up the work, col-
lecting more samples and working on ways to extract the riches from
the oceans.
The gold stubbornly refused to appear. What was wrong? They car-
ried out more analyses, more carefully—the amount of gold went
down and down with successive tests. Their dreams of wealth, and of
rescuing their country, fell apart. Instead of 6 milligrams in a tonne
of seawater, there turned out to be about a hundredth of a milligram—
nowhere near enough to extract for profit, not even for a chemist of
Haber's powers. What had gone wrong?
The answer was laughably simple: contamination. Gold in the wed-
ding rings that the scientists were wearing, in their spectacle frames,