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The World's Greatest Fix. A History of Nitrogen and Agriculture. By G. J. Leigh

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hand, students in advanced courses will
benefit from studying the metal-catalyzed reactions that are discussed in
Modern Organonickel Chemistry, and
the book will certainly give them a good
introduction to the world of metalcatalyzed organic synthetic chemistry.
Yoshiro Masuyama
Department of Chemistry
Sophia University (Japan)
The World’s Greatest Fix
A History of Nitrogen and Agriculture. By G. J. Leigh.
Oxford University
Press, Oxford
2004. 254 pp.,
£ 29.95.—ISBN
“This book tells the story of how
humans have used their ingenuity
throughout our history to maintain soil
fertility and avoid famine through productive agriculture” is the opening sentence of this book with its intriguing title
by G. Jeff Leigh. That first sentence
promises a lot. It also hints at who
might be attracted to reading this monograph, and that is anyone who is interested in history, anyone who is interested in science, and also anyone who is
interested in the environment. The title
also provides the focus for the book,
which is nitrogen. One would infer from
the title that nitrogen and agriculture are
somehow connected. That connection is
emphasized early in the book, starting
with Chapter 1.
Of the seven chapters that make up
this monograph, the first is the primer
for the book, setting up what the author
is trying to do, and what the reader
needs to know about chemistry (in a
section aptly titled “All the nitrogen
chemistry you need to know”), about
biology, and about industrial chemistry.
The second and third chapters give a
history of agriculture, which ranges from
the beginning of civilization, with some
intriguing connections to the various
cultures around the world, to the end
of the 19th century. Apparently, the
success of the longer-lived empires in
Egypt, in Central America, in China,
and in Europe (the Romans) all correlate with some recognition of basic
farming techniques such as crop rotations and the use of manure as a
fertilizer. The description of the fall of
the Mayan culture, as a direct consequence of the people-s lack of sophistication in the agricultural realm, is compelling. It is interesting to read how two
successful cultures, those of the Chinese
and the Romans, had both written “how
to” manuals that described methods to
be better farmers. A more focused
account of the history of agriculture in
England is given in Chapter 3. Some of
the early attempts to apply scientific
methods to plant growth are described;
the classic tree-growing experiment of
van Helmont is recounted, and various
interpretations are described. The word
“nitre” has a long history, and the author
unravels its first use, its many misinterpretations, and its final and correct
identification. The discussion of the use
of guano as a fertilizer and the resulting
nitrate wars is fascinating from the
viewpoints of discovery, the politics,
and the rapid depletion of this rich
source of nitrogen. An overarching
theme is the fact that many distinguished scholars had predicted the
downfall of western civilization (i.e.,
wheat eaters), on the basis of the rate
of population increase in relation to the
ability to feed these people in the future.
The predictions by Malthus and the
Club of Rome provided both incentive
and controversy, so much so that Malthus-s original publication underwent
many editions, the final one of which
was apparently at odds with the original.
The fourth chapter is a tour de force
on nitrogen, its discovery, and some of
the controversies that surrounded this
simple, abundant small molecule.
Names such as Lavoisier, Cavendish,
Rutherford (Daniel not Ernest), Davy,
von Liebig, and many others populate
this important chapter. It is here that
Leigh interleaves the theories about
nitrogen in the air and nitrogen in the
0 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
soil. During the 19th century, many
eminent scientists did not believe that
nitrogen from the atmosphere could be
converted into ammonia, to be used by
plants. The account of how this was
eventually proven to be possible is
fascinating, and it goes to the very
heart of scientific investigation and
persistence. The breakthrough experiments by Hellriegel and Wilfarth in
Prussia, which showed that pea plants
could fix nitrogen only when they were
exposed to nonsterile soil, opened up
the whole area of biological nitrogen
fixation. The discovery of a connection
with the root nodules and some infectious agent, a bacterium that infected
the soil, was a major leap forward in this
Chapter 5 moves on to a discussion
of the various industrial processes that
involve nitrogen, including the Norwegian arc process, the cyanamide process,
and the Haber–Bosch process. But these
are not just accounts of the chemistry
and conditions—the discussion here
goes further by trying to understand
something about the people who were
attempting to make these processes
work. The highs and lows of Fritz
Haber-s career are recounted here, but
not as a focal point, rather for the sake
of completeness. More important and
fascinating to read is the account of why
countries were racing to find alternative
sources of nitrate (for explosives), and
how they accomplished this. The fact
that Haber and Bosch were the eventual
winners is well known, but what might
not be so evident is how, after the First
World War, other countries tried to get
the secrets of this technology out of the
BASF staff, apparently without success.
Chapter 6 moves back to discuss the
mystery of biological nitrogen fixation,
and includes the sequence of reports and
discoveries that led to our present
understanding of the nitrogenase
enzyme. It is only since 1960 that a
reliable and reproducible method for
extracting the enzyme has become available. This important discovery by the
DuPont company has certainly accelerated knowledge in this area. But what
was still unknown, and remains so to this
day, is how the enzyme accomplishes the
conversion of dinitrogen into ammonia
under ambient conditions. Leigh discusses very recent work that outlines the
Angew. Chem. Int. Ed. 2006, 45, 2657 – 2659
structure of the active site of the enzyme
from Azotobacter vinelandii, and summarizes model studies using molybdenum coordination complexes, showing
the reader where the limit of the present
knowledge envelope lies. But the story
of nitrogen fixation is still very much a
Chapter 7 presents a thorough and
balanced discussion about the environmental impact of humans on the world,
especially in the context of food production, fertilizer use, and pollution.
The use of “organic” fertilizers is often
touted as the environmentally friendly
method of growing food. But it is clear
that the world will continue to need
“inorganic” fertilizers such as ammonia
Angew. Chem. Int. Ed. 2006, 45, 2657 – 2659
and phosphates, to continue to feed the
global population. The increased concentrations of nitrates in the soil and in
the water, and its effects on human
health, are discussed in a very clear and
scientific way, with graphs, tables, and
lots of data to back up the statements.
This is a very complex problem that is
not simple to define or unravel. However, Leigh-s very clear analysis of the
situation in the context of risk assessment is compelling.
G. Jeff Leigh played a central role in
the Nitrogen Fixation Unit that was set
up in the mid-1960s at Sussex University.
Working alongside Joseph Chatt in a
collaborative environment, he was well
positioned to view the whole area of
nitrogen fixation, from the pure chemistry focus to the biological and agricultural potential applications. This monograph clearly shows that he also has a
knack for connecting the fascinating
history of civilization to this simple yet
abundant small molecule, molecular
nitrogen. This book is a unique and
enjoyable read from a knowledgeable
Michael D. Fryzuk
Department of Chemistry
University of British Columbia
Vancouver (Canada)
DOI: 10.1002/anie.200485364
0 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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fix, nitrogen, history, agriculture, greatest, leigh, world
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