Friday, March 30, 2018

Trotting Ahead of Malthus: The Fodder/Horse/Coal/Lime Cycle

A repost from Unenumerated, July 2014:
Progress in the Malthusian isocline in England from the 13th through 19th centuries, as, among many other factors, horses slowly replaced oxen for farm work and transport, the ratio of draft animals to people increased, and more arable land was devoted to fodder relative to food.(click to enlarge)
I have previously discussed Great Britain's unprecedented escape from the Malthusian trap. Such escapes require virtuous cycles, i.e. positive feedback loops that allow productive capital to accumulate faster than it is destroyed. There are a number of these in Britain in the era of escape from the Black Plague to the 19th century, but two of the biggest involved transportation.

One of these that I've identified was the fodder/horse/coal/lime cycle. More and better fodder led to more and stronger horses, which hauled (among other things) coal from the mines, initially little more than quarries, that had started opening up in northeastern England by the 13th century. Coal, like wood, was very costly to transport by land, but relatively cheap to ship by sea or navigable river. As fodder improved, horses came to replace oxen in the expensive step transporting goods, including coal, from mine, farm, or workshop to port and from port to site of consumption. Many other regions (e.g. in Belgium and China) had readily accessible coal, but none developed this virtuous cycle so extensively and early.

Among the early uses of coal was for heating, fuel for certain industrial processes that required heat (e.g. in brewing beer), and, most interestingly, for burning lime. Burned lime, slaked with water, could unlike the limestone it came from be easily ground into a fine powder. This great increase in the surface area of this chemical base, which let it de-acidify the soils on which it was applied. The soils of Britain tend to be rather acidic, which allows poisonous minerals, such as aluminum, to absorb into plants and blocks the absorption of needed nutrients (especially NPK -- nitrogen, phosphorous, and potassium). The application of lime thus increased the productivity of fields for growing both food and fodder, completing the virtuous cycle. This cycle operated most strongly during the period of the consistent progress in the English Malthusian isocline from the 15th through 19th centuries.

Another, related, but even more important cycle was the horse/transport and institutions/markets/specialization cycle....MUCH MORE