Rapid outward expansion required longer journeys to work and shopping for the middle class office workers and housewives. The working-class generally did not own automobiles until after 1945; they typically walked to nearby factories and patronized small neighborhood stores. The middle class demanded a better transportation system. Slow horse-drawn streetcars and faster electric trolleys were the rage in the 1880s. In the horse-drawn era, streets were unpaved and covered with dirt or gravel. However, this produced uneven wear, opened new hazards for pedestrians, and made for dangerous potholes for bicycles and for motor vehicles. Manhattan alone had 130,000 horses in 1900, pulling streetcars, delivery wagons, and private carriages, and leaving their waste behind. They were not fast, and pedestrians could dodge and scramble their way across the crowded streets. In small towns people mostly walked to their destination so they continued to rely on dirt and gravel into the 1920s. Larger cities had much more complex transportation needs. They wanted better streets, so they paved them with wood or granite blocks. In 1890, a third of Chicago's 2000 miles of streets were paved, chiefly with wooden blocks, which gave better traction than mud. Brick surfacing was a good compromise, but even better was asphalt paving. With London and Paris as models, Washington laid 400,000 square yards of asphalt paving by 1882, and served as a model for Buffalo, Philadelphia, and elsewhere. By the end of the century, American cities boasted 30 million square yards of asphalt paving, followed by brick construction. Street-level electric trolleys moved at 12 miles per hour, and became the main transportation service for middle class shoppers and office workers. Big-city streets became paths for faster and larger and more dangerous vehicles, the pedestrians beware. In the largest cities, street railways were elevated, which increased their speed and lessened their dangers. Boston built the first subway in the 1890s followed by New York a decade later.