In lieu of an abstract, here is a brief excerpt of the content:

i n t r o d u c t i o n Thinking about Horses Humans constructed their understanding and use of horses over millennia. The biologist Jared Diamond’s important work notes that horses were perfect domesticable animals with dominance hierarchies, a tolerance for other species, genetic malleability, and herding instincts. In prehistory, the availability of such animals led to the enormous growth and wealth of human populations in areas of the globe where horses existed or could be easily imported. Humans first tamed horses for meat, leather, and manure perhaps as early as 14,000 BCE, even before they were used to carry or pull things. Such beasts of burden allowed significant long-distance trade and economic specialization. By the start of the Christian era, horse-based societies held all the trump cards—more productive agriculture (horses pulled plows, provided fertilizer, and eventually found their way to the dinner table), more long-distance trade, and military supremacy.1 The nineteenth-century city represented the climax of human exploitation of horse power. Humans could not have built nor lived in the giant, wealth-generating metropoles that emerged in that century without horses. Horses, too, bene fited from the new human ecology. Their populations boomed, and the urban horse, although probably working harder than his rural counterpart, was undoubtedly better fed, better housed, and protected from cruelty. To the extent that it can be determined, the urban horse was also larger and longer lived than were farm animals. Thus, the relationship was symbiotic—horses could not have survived as a species without human intervention, and dense human populations frequently relied on horses. Almost every other species of large grazing mammal disappeared; for example, the original, wild North American horse was unable to defend its territory against smaller predators, including humans. The European horse survived because it found an ecological niche as a partner for humans. In a sense this was co-evolution, not domination.2 Mechanizing the Natural Nineteenth-century business owners valued horses for the profits that they produced. To them, horses were mostly machines, as the French philosopher René Descartes had argued, not living organisms and certainly not moral beings. Robert Bakewell, the famous pioneer of modern breeding, for instance, “sought to discover the animal which was the best machine for turning food into money.” Productive Horse Husbandry, a frequently reprinted treatise, included a chapter, “The Horse as a Machine,” which argued that the best horses were those that produced the most work for the least food (fuel). Another tough-minded author noted that “the horse is looked on as a machine, for sentiment pays no dividend.” In the “rational” world of the nineteenth century, people increasingly viewed horses as property or living machines subject to technical refinement, not as sentient beings.3 This mechanistic view of animals was most evident when humans compared draft animals to industrial machines. The Journal of the Franklin Institute noted in 1833, “The name of horse power has become technical, and is applied to any apparatus by means of which a horse is made to exert his power in propelling machinery .” The major aim of the “horse power” machine was to convert the “linear , ambulatory, slightly rhythmic gait of the animal—horse or ox—to the rotary motion required by most machinery,” usually through gears. Horses powered machinery in mills and factories, raised and pumped water, sawed wood, drove hoisting devices and construction equipment, and even provided power to drive ferries via paddle wheels and land vehicles via turntables geared to wheels. Numerous museums contain artifacts of such machinery. Obviously, horses hauled things as well.4 The problems of engineering with living machines needed to be worked out. How much power could a horse supply? Implicitly this involved knowing how much power an engine or a human could provide, since the point of the comparison was to facilitate engineering decisions about when to adopt human power, when to adopt horse power, and when to adopt steam power. Post-Renaissance European philosophers and scientists had speculated about this question. A scienti fic approach to comparing the strength of the two species first appeared in 1699 in the initial volume of Memoires of the French Academy. The Memoires reported a discussion among savants about the horizontal pushing force of a horse and a man. Horses, they speculated, were equal to six or seven men in their power output. Later empirical research would produce results not far di¤erent from this. 2...

Share