POWER, FOOD AND SLAVERY
“I sell here, Sir, what all the world desires to have—POWER.” So said Mr Boulton of the famous firm of Boulton and Watt when he conducted James Boswell around his works. Boswell, in his Life of Samuel Johnson (22nd March, 1776), remarks that he would never forget Boulton's expression. It was indeed a telling phrase and one that must have been repeated to a succession of visitors. Boulton, of course, was strictly accurate in the engineering sense, first defined by his partner, but he was also making the point that their engines create wealth and this leads to power in the more general sense of physical and economic strength, ability, influence and authority. He was selling power in all its manifestations. This relation, between mechanical power and wealth is of fundamental importance in creating a high standard of living; the two are inextricably linked and this connection has been one of the important, underlying determinants of history.
To understand the significance of prime movers it is necessary to understand their importance not only in generating mechanical power but also in generating wealth. In this chapter, therefore, the coupling of energy consumption and wealth is examined more closely. For pre-industrial societies, and the ancient civilisations in particular, the major source of energy was food, which was realised as useful work by muscular exertion, usually by slaves. It is appropriate therefore to examine the energy needs of agriculture and to explain the dramatic change in agriculture from its ancient use in producing essential food energy to its modern condition of absorbing more energy than the food product contains. It is also necessary to examine and explain, though not to condone, the ancient and persistent reliance on slavery. Mechanisation eventually released the slave from his bondage and the farm labourer from his drudgery, but it has jeopardised modern agriculture by making it over-reliant on fossil fuel energy.