"The Reformation opened the door a little wider. But Pentecostalism didn't really take off until the year 1900, when a small group of Bible-college students in Kansas began to speak in tongues. They spread the practice to Texas. There it became known as the revival movement. It spread like wildfire, all across the United States, and then the world, reaching China and India in 1906. The twentieth century's mass media, high literacy rates, and high-speed transportation all served as superb vectors for the infection. In a packed revival hall or a Third World refugee encampment, glossolalia spread from one person to the next as fast as panic. By the eighties, the number of Pentecostals worldwide numbered in the tens of millions.