The opposition illustrates the shaping of technology by cultural values.

The question that remains unresolved is why the public reacted so strongly to a technology that we now regard as environmentally desirable, especially relative to the automobile.

In the late nineteenth century, most American cities had inadequate sewage systems, offered spotty refuse disposal and street cleaning, permitted appalling air pollution from coal-burning factories and left many streets practically unpaved. Why urban residents objected so strongly to a technology that promised to improve urban transportation while eliminating tons of horse droppings remains puzzling.

In part the answer lies in the culture of the street. For the mass of urban residents, mechanized street transportation threatened to destroy the traditional functions of the streets as spaces of social interaction. In most of the nineteenth century cities the houses fronted directly onto the streets. Backyards were often rendered useless by refuse and by leaking toilets. Whenever they could, urban residents used streets for socializing and recreation. The streets were especially important play area for children. Horse-drawn vehicles interfered with the social function of the street but their low speed kept the interference to tolerable level. Mechanized street transportation, in contrast, threatened these social functions.