there—and most often a movement beginning in any one district has sooner or later had some contact with every other district. There is no such division in Islam as that which prevents the average English churchman from knowing about and appreciating a religious movement at work in the Coptic or Serbian church. The common life of Islam is largely based on the use of the Arabic language as the medium of daily life, or at least of prayer and the medium of scholarship, and this was extremely effective before the inclusion of large Turkish and Indian elements which have never really become Arabic speaking. It was this which made the Arabic speaking community of Islam so favourable a medium of cultural transmission. The 'Umayyad period was a marking time during which this common life was being evolved, and with it was evolved necessarily the bitterness of sectarian and faction divisions which always result when divergent types are in too close contact with one another.
