To travel in the desert is in one respect curiously akin to travelling on the sea: it gives you no premonition of the changed environment to which the days of journeying are conducting you. When you set sail from a familiar shore you enter on a course from which the usual landmarks of daily existence have been swept away. What has become of the march of time? Dawn leads to noon, noon to sunset, sunset to the night; but night breaks into a dawn indistinguishable from the last, the same sky above, the same sea on every side, the same planks beneath your feet. Is it indeed another day? or is it yesterday lived over again? Then on a sudden you touch the land and find that that recurring day has carried you round half the globe. So it is in the desert. You rise and look out upon the same landscape that greeted you before--the contour of the hills may have altered ever so slightly, the hollow that holds your camp has deepened by a few yards since last week, the limitless sweep of the plain was not hidden a fortnight ago by that little mound; but here are the same people about you, speaking of the same things, here is the same path to be followed, yes, even the seasons are the same, and the dusty face of the desert is too old to flush at the advent of spring or to be wreathed in autumn garlands of gold and scarlet. Yet at the end of a long interval composed of periods recurrent and alike, you look round and see that the whole face of the universe has changed. When we reached Kerbelâ we passed into a world of which the aspect and the associations were entirely new to me. I had set out from an Arab town in North Syria, and I emerged in a Persian city linked historically with the Holy Places, with the first struggles and the only great schism of Islâm. At Kerbelâ was enacted the tragedy of the death of Ḥussein, son of ’Alî ibn abi Tâlib; the place has grown up round the mosque that holds his tomb, and to one half of those who profess the Mohammadan creed it is a goal no less sacred than Mecca. But it was not the golden dome of Ḥussein, though it covers the richest treasure of offerings possessed by any known shrine (unless the treasure in ’Alî’s tomb of Nejef touch a yet higher value), nor yet the presence of the green-robed Persians, narrow of soul, austere and stern of countenance--it was not the wealth and fame of the Shî’ah sanctuary that made the strongest assault upon the imagination. It was the sense of having reached those regions which saw the founding of imperial Islâm, regions which remained for many centuries the seat of the paramount ruler, the Commander of the Faithful. Within the compass of a two-days’ journey lay the battlefield of Ḳâdisîyah, where Khâlid ibn u’l Walîd overthrew at once and for ever the Sassanian power. Chosroes with his hosts, his satraps, his Arab allies--those princes of the house of Mundhîr whose capital was one of the first cradles of Arab culture--stepped back at his coming into the shadowy past; their cities