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Topic of Book
Wrigley examines the British Industrial Revolution with particular focus on energy.
If you are looking for a good overview of the British Industrial Revolution, I would not recommend this book. While Wrigley makes some interesting observations on the importance of energy, it misses so much else. And other books are more useful in understanding energy.
- All pre-Industrial economies were organic. They relied on energy sources from plants and animals. They relied on muscle power, whether human muscles or animal muscles.
- This made long-term economic development very difficult because as the economy grows, it will be forced to consume more plants and animals. At some point natural land limits would be reached that stop growth.
- The Industrial Revolution signaled a shift to mineral energy, particularly coal.
- Once the steam engine could be created, England could produce huge amounts of non-organic mechanical energy. This removed the biological limits to economic growth.
- Coal did not create the Industrial Revolution but it enabled the economic expansion to continue rather than being brought to a halt by energy constraints.
Important Quotes from Book
Pre-industrial societies had access only to very limited energy supplies. As long as mechanical energy came principally from human or animal muscle and heat energy from wood, the maximum attainable level of productivity was bound to be low. Exploitation of a new source of energy in the form of coal provided an escape route from the constraints of an organic economy but also brought novel dangers.
In my view the most important single issue on which to focus in trying to gain a clearer understanding of the industrial revolution is not how the period of more rapid growth began, but why it did not come to an end.
The book has a particular form. It marshals the discussion of the industrial revolution round a single, central theme, the history of energy availability and use.
The book has a more limited purpose than general treatments of the industrial revolution. It seeks above all to provide an explanation not for an acceleration in economic growth but for the absence of a subsequent deceleration.
All economies which developed in the wake of the neolithic food revolution may be termed organic. In organic economies not only was the land the source of food, it was also the source directly or indirectly of all the material products of use to man. All industrial production depended upon vegetable or animal raw materials… . Thus the production horizon for all organic economies was set by the annual cycle of plant growth. This set physical and biological limits to the possible scale of production. Organic economies therefore differed fundamentally from economies transformed by the industrial revolution since many of the industries which grew most rapidly thereafter made little or no use of organic raw materials. Above all, access to a mineral rather than a vegetable energy source expanded the production horizon decisively.
All types of material production involve the expenditure of energy. Wielding a spade or driving a plough, mining copper ore, operating a loom, smelting iron, or baking bricks all mean making use of either heat or mechanical energy. The same is true of many other aspects of economic activity. The transport of raw materials and finished products, for example, is as much a part of the production process as a whole as is farming or manufacture. Transport often involves a large expenditure of energy, and, although the quantity of energy needed may be smaller, many other service industries also require some energy expenditure. In all organic economies this fact necessarily limited the opportunity for growth.
The total quantity of energy arriving each year on the surface of the earth from the sun is enormous, far exceeding the amount of energy expended each year across the world today, but in organic economies human access to this superabundant flow of energy was principally through plant photosynthesis. Plant growth was the sole source of sustenance for both people and animals, whether herbivores, carnivores, or omnivores. Plant photosynthesis is the food base of all living organisms. This is as true of a pride of lions as of a herd of antelopes. Photosynthesis, however, is an inefficient process. Estimates of its efficiency in converting the incoming stream of energy from the sun normally lie only in the range between 0.1 and 0.4 per cent of the energy arriving on a given surface.
The mechanical energy derived from muscle power was only a limited fraction of the calories consumed in food and fodder because men and women in common with all warm-blooded creatures must devote a large part of their food intake to basic body maintenance. For example, about 1,500 kilocalories are needed daily to keep a man alive even if no work is performed. Thus if the daily food intake is 2,500 kilocalories only 40 per cent of the energy consumed is available for productive work.
A factor of great significance in organic economies was the ratio of available animal muscle to human muscle.
Heat energy like muscle energy depended on plant photosynthesis. Burning wood provided the great bulk of the heat energy consumed. Many industrial processes required large quantities of heat energy. Glass manufacture, brickmaking, beer brewing, textile dyeing, metal smelting and working, lime burning, and many similar processes required much heat energy. Wood was the dominant, indeed in most organic economies virtually the sole source of heat energy.
All forms of production in an organic economy were ultimately conditioned and constrained by the character of the process of photosynthesis in plants.
I suggest that one necessary condition for the escape from the constraints of an organic economy was success in gaining access to an energy source which was not subject to the limitations of the annual cycle of insolation and the nature of plant photosynthesis.
The switch to coal may be regarded as a necessary condition for the industrial revolution but it was not in itself a sufficient cause.
There was a notable contrast between England and her near neighbours both in the sixteenth and in the nineteenth century but the nature of the contrast changed fundamentally. At the beginning of the period England was a laggard economy. It was one of the least urbanised countries in Europe in the sixteenth century.
Two centuries later the contrasts were largely in the opposite direction. At the time of the Great Exhibition in 1851 England had become the most urbanised country in Europe, with London as its biggest city.6 London was the largest and most influential single centre of commercial expertise and the chief vehicle for international investment, the hub of world trade. Approximately two-thirds of the European production of cotton textiles took place in the UK.7 The comparable percentages for iron production and coal output were 64 and 76 per cent.
In the mid-sixteenth century, coal, though it already supplied a tenth of English energy consumption, was substantially less important than human and animal muscle power, and firewood was the prime source of heat energy. By 1700 about half of the total energy consumption of England came from coal. At the end of the eighteenth century the proportion exceeded three-quarters, and by 1850 was over 90 per cent. Much coal was consumed for domestic purposes. Until the end of the seventeenth century it is likely that domestic heating and cooking accounted for more than half the total consumption, but by the early nineteenth century this figure appears to have declined to roughly one third of the total.
Coal provided ‘ghost acres’ on a huge scale.
By the end of the seventeenth century the switch to coal was largely complete in brewing, lime burning, salt production, dye industries, brick and tile making, glassmaking, alum boiling, sugar and soap production, smithying, and a wide range of metal processing trades… ‘By 1700 coal was the preferred fuel of almost all fuel-consuming industries, and access to coal supplies had already begun to exert a determining influence over industrial location.’
The final step in the process by which the use of fossil fuel broke the bonds of the organic economy was taken with the discovery of ways of using the energy in steam to extend the breakthrough in the availability of heat energy to overcome the mechanical energy bottleneck also.
The rise in the volume of coal production created an incentive not only to invest in more efficient land transport but also to construct canals. A large proportion of the traffic on most canals consisted of coal.
It is one of the minor paradoxes of the industrial revolution that, although the increasing use of coal was central to the solution of the problem which had made protracted growth impossible in organic economies, there was no revolutionary change in productivity within the coal industry itself.
Viewed in feedback terms, therefore, the key change which defines the industrial revolution was the replacement of negative by positive feedback within the growth process, and in particular the gradual elimination of the fixed supply of land as a constraint which prevented indefinite growth.
In the mid-sixteenth century mechanical energy was derived almost entirely from human and animal muscle which between them accounted for more than half of the total of energy consumption. Heat energy came mainly from wood, which was roughly three times as important as coal. Energy consumption per head quintupled over the three centuries but if coal is excluded from the picture there is a modest decline rather than striking growth.
The strategic significance of coal in the industrial revolution did not consist principally in generating an early momentum, in causing a ‘take-off: it lay in the fact that it enabled expansion to continue rather than being brought to a halt by the energy constraints inherent in organic economies which forbade sustained exponential growth over a lengthy period.
The importance of coal as an energy source, though sometimes left largely unremarked, has been widely recognised. Its importance in bringing about radical improvements in transport provision has perhaps been less fully acknowledged. It was a basic weakness of organic economies that heavy investment in transport infrastructure was unlikely to produce savings sufficient to justify the expenditure involved. The increasing volume of coal production changed this situation.
One of the best ways of defining the essence of the industrial revolution is to describe it as the escape from the constraints of an organic economy. Civilisations of high sophistication developed at times in many places in the wake of the neolithic food revolution: in China, India, Egypt, the valleys of the Tigris and Euphrates, Greece, and Rome, among others. Their achievements in many spheres of human endeavour match or surpass those of modern societies; in literature, painting, sculpture, and philosophy, for example, their best work will always command admiration. Some built vast empires and maintained them for centuries, even millennia. They traded over great distances and had access to a very wide range of products. Their elites commanded notable wealth and could live in luxury. Yet invariably the bulk of the population was poor once the land was fully settled; and it seemed beyond human endeavour to alter this state of affairs.