Again the two signs of sovereignty for Muslims are that the name of the sovereign should be on the coinage and that he should be prayed for in the Friday sermon (_khutba_). In India, the custom seems to be to pray for “the ruler of the age” without name; then each worshipper can apply it as he chooses. But there has crept in a custom in a few mosques of praying for the Ottoman Sultan as the Khalifa; the English government busies itself little with these things until compelled, and the custom will doubtless spread. The Ottoman Sultan is certainly next greatest to the Emperor of India and would seem, as a Muslim ruling Muslims, to have an unassailable position. But in his case also difficult and ambiguous constitutional questions can be raised. He has claimed the Khalifate, as we have seen, since 1538, but the claim is a shaky one and brings awkward responsibilities. As stated at the present day, it has five grounds. First, _de facto_ right; the Ottoman Sultan won his title by the sword and holds it by the sword. Second, election; this form has been already described. Third, nomination by the last Abbasid Khalifa of Egypt; so Abu Bakr nominated Umar to succeed him, and precedent is everything in Islam. Fourth, possession and guardianship of the two Harams, or Sacred Cities, Mecca and al-Madina. Fifth, possession of some relics of the Prophet saved from the sack of Baghdad and delivered to Sultan Salim, on his conquest of Egypt, by the last Abbasid. But these all shatter against the fixed fact that absolutely accepted traditions from the Prophet assert that the Khalifa must be of the family of Quraysh; so long as there are two left of that tribe, one must be Khalifa and the other his helper. Still, here, as everywhere, the principal of Ijma, Agreement of the Muslim people, (see p. 105) comes in and must be reckoned with. These very traditions are probably an expression in concrete form of popular agreement. The Khalifate itself is confessedly based upon agreement. The canon lawyers state the case thus: The Imamites and Isma‘ilians hold that the appointment of a leader is incumbent upon God. There is only the difference that the Imamites say that a leader is necessary in order to maintain the laws unimpaired, while the Isma‘ilians regard him as essential in order to give instruction about God. The Kharijites, on the other hand, recognize no fundamental need of an Imam; he is only allowable. Some of them held that he should be appointed in time of public trouble to do away with the trouble, thus a kind of dictator; others, in time of peace, because only then can the people agree. The Mu‘tazilites and the Zaydites held that it was for man to appoint, but that the necessity was based on reason; men needed such a leader. Yet some Mu‘tazilites taught that the basis was partly reason and partly obedience to tradition. On the other hand, the Sunnites hold that the appointment of an Imam is incumbent upon men and that the basis