Streetcars in North America Streetcars in North America Electric streetcars or trolley(car)s (North American English for the European word "tram") were once the chief mode of public transit in hundreds of North American cities and towns. Most of the original urban streetcar systems were either dismantled in the mid-20th century or converted to other modes of operation, such as light rail. Today, only Toronto still operates a streetcar network essentially unchanged in layout and mode of operation. Older surviving lines and systems in Boston, Cleveland, Mexico City, Newark, Philadelphia, Pittsburgh, and San Francisco were often infrastructure-heavy systems with tunnels, dedicated right-of-way, and long travel
Population Association of America Population Association of America The Population Association of America (PAA) is a non-profit scientific professional association dedicated to the study of issues related to population and demography. According to the website of the History Committee of the Population Association of America, the PAA was conceived on December 15, 1930 at a meeting in the office of Henry Pratt Fairchild at New York University. It was an offshoot of the American National Committee of the International Union for the Scientific Study of Population (IUSSP) which had been formed in 1927 with Raymond Pearl of Johns Hopkins University as its first President.