Bell began a series of public demonstrations and lectures to introduce the new invention to the scientific community as well as the general public. A short time later, his demonstration of an early telephone prototype at the 1876 Centennial Exposition in Philadelphia brought the telephone to international attention. Influential visitors to the exhibition included Emperor Pedro II of Brazil. Later Bell had the opportunity to demonstrate the invention personally to Sir William Thomson (later, Lord Kelvin), a renowned Scottish scientist, as well as to Queen Victoria, who had requested a private audience at Osborne House, her Isle of Wight home. She called the demonstration "most extraordinary". The enthusiasm surrounding Bell's public displays laid the groundwork for universal acceptance of the revolutionary device.

In what city was the 1876 Centennial Exposition?