required to increase the yield per acre of cereals such as wheat, maize, oats and
rye. But these in turn deplete the soil of its essential nutrients, especially
nitrogen. Replacement of the nitrogen was traditionally achieved by crop
rotations and by spreading barnyard manures. Crop rotation involved planting
legumes (such as beans or peas) which were able to utilise nitrogen from the air
and convert it to a mineral form readily assimilated by plants. This helped
replace the nitrogen, but reduced the production of the more profitable cereal
crops. Spreading manure only replaced a small potion of the nitrogen removed
from the soil. As cities grew across Europe, food was exported to them from the
farms and nitrogen was lost in sewers and privies and not returned to the soil,
Coffey, op. cit. (note 3), p. 83.
4. The ready availability of the saltpetre sources was a major factor in the
invention and the commercialisation of a number of modern explosives. In
1900, the USA used almost 50% of its imports of NaNO 3 to make explosives.
Indeed, but for the discovery and exploitation of the Chilean deposits, the
explosives industry as we know it today would have been impossible.
5. Vaclav Smil, Enriching the Earth, MIT Press, (2001). http://mitpress.mit.udu.
ISBN-978-0-262-693134.
6. Sodium nitrate—like all nitrates—is highly soluble and therefore can only
accumulate in arid areas on the planet. The Atacama Desert had not seen any
rain of significance for centuries and these peculiar circumstances allowed
nitrates and the other minerals to accumulate in huge quantities as caliche.
7. As is often the case with recoverable resource estimates, these fears were far too
conservative. An estimate of the country’s resources around 1908 put the
nitrate reserves at 920 Mt, and at an annual rate of 2.7 Mt—the usage per
annum just before WW1—the reserves would have lasted for 340 years. But
920 Mt of NaNO 3 contains less nitrogen than is now fixed in just two years by
the synthesis of ammonia, Smil, op. cit. (note 5), Chap. 3. Even by 1920, ‘200
Years Supply in Chile’ was reported in The Times in an article entitled ‘Nitrates
for War and Peace’, (Tuesday 31 August 1920).
8. The Boer of course were of Dutch-German extraction.
9. (Sir) William Crookes was a man whose opinion had to be respected. He was
born in London on the 17 June 1832. His scientific career began when, at the
age of fifteen, he entered the Royal College of Chemistry in Hanover Square,
London, studying under August Wilhelm von Hofmann. From 1850 to 1854
he filled the position of assistant in the college, and soon embarked upon
original work, on certain new compounds of the element selenium, the
selenocyanides. Leaving the Royal College, in 1854 he became superintendent
of the meteorological department at the Radcliffe Observatory in Oxford, and
in 1855 was appointed lecturer in chemistry at the Chester training college.
From this time his life was passed in London, and devoted mainly to independent work—journalistic, consulting, and academic. In 1859 he founded
the Chemical News, which he edited for many years and conducted on much
3 Germany and ‘Fixation’
93
rye. But these in turn deplete the soil of its essential nutrients, especially
nitrogen. Replacement of the nitrogen was traditionally achieved by crop
rotations and by spreading barnyard manures. Crop rotation involved planting
legumes (such as beans or peas) which were able to utilise nitrogen from the air
and convert it to a mineral form readily assimilated by plants. This helped
replace the nitrogen, but reduced the production of the more profitable cereal
crops. Spreading manure only replaced a small potion of the nitrogen removed
from the soil. As cities grew across Europe, food was exported to them from the
farms and nitrogen was lost in sewers and privies and not returned to the soil,
Coffey, op. cit. (note 3), p. 83.
4. The ready availability of the saltpetre sources was a major factor in the
invention and the commercialisation of a number of modern explosives. In
1900, the USA used almost 50% of its imports of NaNO 3 to make explosives.
Indeed, but for the discovery and exploitation of the Chilean deposits, the
explosives industry as we know it today would have been impossible.
5. Vaclav Smil, Enriching the Earth, MIT Press, (2001). http://mitpress.mit.udu.
ISBN-978-0-262-693134.
6. Sodium nitrate—like all nitrates—is highly soluble and therefore can only
accumulate in arid areas on the planet. The Atacama Desert had not seen any
rain of significance for centuries and these peculiar circumstances allowed
nitrates and the other minerals to accumulate in huge quantities as caliche.
7. As is often the case with recoverable resource estimates, these fears were far too
conservative. An estimate of the country’s resources around 1908 put the
nitrate reserves at 920 Mt, and at an annual rate of 2.7 Mt—the usage per
annum just before WW1—the reserves would have lasted for 340 years. But
920 Mt of NaNO 3 contains less nitrogen than is now fixed in just two years by
the synthesis of ammonia, Smil, op. cit. (note 5), Chap. 3. Even by 1920, ‘200
Years Supply in Chile’ was reported in The Times in an article entitled ‘Nitrates
for War and Peace’, (Tuesday 31 August 1920).
8. The Boer of course were of Dutch-German extraction.
9. (Sir) William Crookes was a man whose opinion had to be respected. He was
born in London on the 17 June 1832. His scientific career began when, at the
age of fifteen, he entered the Royal College of Chemistry in Hanover Square,
London, studying under August Wilhelm von Hofmann. From 1850 to 1854
he filled the position of assistant in the college, and soon embarked upon
original work, on certain new compounds of the element selenium, the
selenocyanides. Leaving the Royal College, in 1854 he became superintendent
of the meteorological department at the Radcliffe Observatory in Oxford, and
in 1855 was appointed lecturer in chemistry at the Chester training college.
From this time his life was passed in London, and devoted mainly to independent work—journalistic, consulting, and academic. In 1859 he founded
the Chemical News, which he edited for many years and conducted on much
3 Germany and ‘Fixation’
93