^{page 905 note 1} The payment of taxes, being dependent on the gathering of the crops in the harvest, Wag naturally effected according to the solar year.

^{page 906 note 1} The Egyptian Naurūz (Nairūz) is always on the 29th (or 30th) August (Julian) but the Persian Naurūz was receding each seven years one day in the Julian year.

^{page 907 note 1} The era of the Deluge will be discussed in this article (vid. infra No. 13).

^{page 907 note 2} La réforme du calendrier, Leyd.

^{page 907 note 3} The work is a Persian translation of the Arabic original composed by Ḥasan ibn Muḥammad ibn Ḥasan Qummī in about A.H. 378.

^{page 908 note 1} The reading of this word is izdilāf in Ṣubḥ al-‘shā of Qalqashandī (vol. 2, p. 388Google Scholar) as well as in Shīfa’ al-‘īl of Khafājī (Egyptian, ed. 1282, pp. 28 and 116)Google Scholar, on the authority of Nuwairī in Nihāyat al-arab. Khafājī in explaining the word asmmeaning the intermixing of the years adds that in his time the scribes called this operation taḥivīl. However, the spelling in the book of Ru'ainī (vide infra) where several times the word is clearly written izdilāq and the Turkish translation sīvīsh (pronounced sivish) make me hesitate to decide in favour of the “ f ‘ ending which was adopted by Wiet, Fagnan, and Kremer.

^{page 908 note 2} The Turkish translation of the same word (sivish) was used later for the same operation in the Turkish equivalent of the Kh. year, namely, māliyya year. Both words mean “ sliding ”.

^{page 909 note 1} According to Ibn al-Jawzī (al-Muntaẓam, Brit. Mus. Or. 3004, fol. 78a) Ṣūlī died in the month of Sha‘bān 243.

^{page 909 note 2} According to Ibn al-Jawzī (ibid., fol. 846), Mutawakkil entered Damascus in the month of Ṣafar 244, i.e. a few weeks after Naurūz.

^{page 910 note 1} The question of choosing the 17th June for the new and stable Naurūz and its reason is again not simple. In the first place, there is another version of the story of this reform, attributed to the famous al-Balāḏẖhuri, who is said to have been present in the audience-hall of Mutawakkil when Ṣūlī read the draft of the circular letters relating to the postponement of the taxation (or of Naurūz) before the Caliph. According to this version, which we find in Irshād al-arib of Yāqūt (GMS., vi, 2, p. 128Google Scholar), and in Ḵẖiṭaṭ of Maqrīzī (Cairo, ed., vol. i, p. 274)Google Scholar, the Naurūz was to be moved to the 5th June (and not to the 17th). Ṣafadī in al-Wafī bi l-wafayāī (seeJA., 1911, p. 282Google Scholar) has also the same version of the story but with the date of new Naurūz as 27th June instead of 17th. Moreover, leaving aside this version and accepting Ṭabarī's and Bīrūnī's reports, we still have difficulty in discovering the reason why the 17th June was chosen instead of 16th. The principle must have been certainly the idea of bringing back the Naurūz to the same Julian day on which it had fallen on the accession year of Yazdegerd III, the last Sassanian King, i.e. to the beginning of the Yazdegerdian era. But the advisers of the Caliph, instead of ascertaining the said position by dividing 225 or 226, the number of the years elapsed since, by 4 and by considering the whole number of the quotient, i.e. 56 as representing the number of days Naurūz had receded in the interval between the two dates (that of the accession of Yazdegerd and that of the reform), have apparently taken the next whole number, i.e. 57, by completing the mixed number of the quotient to a higher integer. Counting then 57 days forward from the 21st April on which Naurūz fell in their time, they reached the 17th June with one day of error.

^{page 910 note 2} The year 279 was, however, the right time for the operation as it was the year 278 in which no Naurūz fell and therefore no neglect can be attributed to the predecessor of Mu'taḍid.

^{page 910 note 3} The right times for “ sliding ” were, however, A.H. 210 and 313 and not 208 and 308.

^{page 911 note 1} The statements of Maqrīzī on all the points relating to the “ sliding ” are based on older sources; for instance, in the matter of “ sliding ” by order of Mutawakkil he quotes an author of the sixth century A.H. who in his turn quotes a man no less than the chief tax-collector for the said Caliph himself. For fuller details the reader must be referred to Maqrīzī and Qalqashandī, whose statements are very similar. The “ sliding ” of only one year in 351 proves that the “ sliding ” due at the end of the previous cycle (313) had actually taken place.

^{page 911 note 2} The Persian New Year in A.H. 351 was on 15th Ṣafar.

^{page 913 note 1} The Muḥammadan theologians and philosophers attribute to Naẓẓām, the famous Mu'tazilite theologian and dialectician of the early part of the third century A.H., the hardly imaginable theory of the possibility of the transfer of a moving body from one point to another distant (not immediate) point without crossing the interval. This action is called, in the Arabian philosophic technology, ṭafra (meaning jumping or springing) which word is used by Waṣṣāf (see also Horten, M., ZDMG., 63, p. 782Google Scholar).

^{page 914 note 1} This is the variant reading in Maqrīzī's book. Qalqashandī has only 499.

^{page 914 note 2} Neugebauer in his Hilfstafeln zur technischen Chronologie (Kiel, 1937) gives a table for the Egyptian Kh. years from A.H. 366 to 496 with the corresponding lunar Hijra years as well as the Christian and Panodoros dates (table 32, p. 56). This table, which is apparently worked out by the said author, is, no doubt, based on the supposition that the necessary “ sliding ” due at the end of each cycle between the two dates has been always regularly effected. However, since the “ sliding ” did not take place regularly, as we have seen, the table cannot be helpful for ascertaining the strictly correct Kh. dates.

^{page 916 note 1} The bill was approved by the parliament on 31st March of the same year.

^{page 917 note 1} Some others, perhaps more realist, however, finding the use of an era relating to the reign of a king, after his death, unreasonable, started a new era in his memory which began with the year following the last year of his reign. This last era forms the subject of section 7 of this article.

^{page 917 note 2} A.Y. means in this article the Yazdegerdian era.

^{page 918 note 1} The year of the Iranian Zoroastrians and that of the Kadīmī sect among the Indian Parsis began in A.D. 1938 with the 7th August, whereas the year of the Shāhanshāhī or Rasmī sect in India began with the 6th September. In recent times a third party called Faṣlĩs appeared in India who have adopted the vernal equinox day as the beginning of theīr year.

^{page 918 note 2} The real name of this era by which it must have been called by those who used it in the first centuries of Islam is not known. Possibly this was also called the era of Yazdegerd as some authors call it so (e.g. Bar-Hebraeus in his Le livre de I’ascension de I’esprit.…). The name of “ Magian era ” is a translation of Tārīḵẖ al-Majūs of Bīrūnī, which is used by that author but not as the name of the era.

^{page 918 note 3} According to Ṭabari and most of the othẹr Muẖammadan historians, the sad end of the last Sassanian ruler in the vicinity of Marv came in the year A.H. 31. Dinawarī (al-Aḵẖhbār aṭ-tiwāl, ed. Guirgas, , p. 149Google Scholar), however, puts it in the year 30 and Mas’udī (Kitab at-tanbīh, p. 103), as well as Ṣā’id ibn Aḥmad al-Andalusi in his Ṭabaqāt alumam (ed. Cheiḵẖho, p. 17)Google Scholar, has the date 32 (beg. 12th August, 652). Accepting the year 31, which seems to be based on the best tradition, Yazdegerd must have been killed after the 23rd August, 651, which was the beginning of the lunar year A.H. 31. On the other hand, since the last known coin of that King bears the date 20 of his reign (see Mordtmann, , ZDMG., 1879, p. 83Google Scholar, and Nöldeke, , Ṭabarī, p. 431)Google Scholar, his death must have occurred before 11th June, A.D. 652. Thus he must have passed away either during the last four months of the Christian year 651 or during the first five months of 652. The first alternative is more probable as it agrees also with one of the relations given by Ṭabarī (i, 2872)Google Scholar, which puts the burying of the King’s body in Istaḵẖr in the early part of the year 31 (possibly in September or October). However, the possibility of the occurrence of the death of Yazdegerd in the 21st year of his reign and even in A.H. 32 as Ṣāa7’id recorded, is not absolutely excluded by a decisive proof. The number given by Ṭabar7ī (i, 1068)Google Scholar, as representing the interval between the Hijrat and the death of the King “according to the Zoroastrians ”, namely 30 years 2 months and 15 days, could even indicate the autumn of the year 652 (20th September), if the 30 years were solar Persian years, though the duration of his actual reign would not be still longer than 19 years and about 4 months if his accession was, as Firdausī tells us, on the 25th day of the 12th Persian month, i.e. 10th June, 633. This date (32 A.H.), however, must be left aside as just an improbable possibility and not more than that.

We have dwelt at some length on this point particularly because of its bearing on the question of the dates of the coins of the Ispahbeds which is discussed below.

^{page 919 note 1} Though Bīrūnī in his last-named book (fol. 26a) says that the Magian era “ is from the year of the perishing of Yazdegerd and not from the [first] year of his reign ] this must not be taken in the strict meaning of the word but as meaning from his death.

^{page 919 note 2} Professor Minorsky, V. suggests (Ḥudūd al-’ālam, p. 356Google Scholar) that the word may be a miswriting for Isfiḏẖyāriyya.

^{page 919 note 3} The word maḏẖab in the text means way and opinion, i.e. the practice.

^{page 919 note 4} This is, as a matter of fact, the difference between any Yazdegerdian date and its Magian correspondent wherever the epagomenae were at the end of the year.

^{page 919 note 5} According to the last-named author the coins of Ṭabarist7ān with this era are found with dates as late as 161 (A.D. 812–13).

^{page 920 note 1} Vasmer, however, in his art7īcle Die Eroberung Tabaristāns dutch die Araber z. Zeīt des Chalīfen al-Manṣūr (Islamica, 1927, p. 98, n. 2), pronounces very correctly in favour of 652 as the beginning of the era, when he differs with Marquart on the dates of the Arabian lunar years corresponding to the different “ṬTabari ” years.

^{page 921 note 1} Unvala, J. M. in his valuable book just published (Coins of Ṭabaristān and some Sassanian coins from Susa, Paris, 1938, p. 35)Google Scholar, ascribes a previous governorship to Sa’id in the year 121 of the so-called Ṭabar7ī era (beg. 12th May, 772 A.D.), apparently relying only on a not very clear date of a unique coin. I am unable to find a confirmation in the sources accessible to me.

^{page 921 note 2} Mordtmann (op. cit., p. Ill) expresses the opinion that the province was occasionally divided into two parts and had two governors.

P.S.␔The Magian era seems to have been in use in all parts of Persia in the early centuries of Islam side by side with the era of Yazdegerd. Mutawakkil in his reform took the latter era as the basis of the calculation and Mu7’tadid took the former. This era continued to be used by the Zoroastrian community for much longer than I first believed. It appears from the colophons of some extant Pahlavi books that the Magian era was still in use by the said community in the sixteenth and seventeenth centuries A.D. In the colophon of the Bundahishn TD², edited by Anklesaria, the date of the copy is given as ‘ the year 975 twenty years after Yazdegerd ’. [According to Anklesaria another manuscript of the same book (DH.) is dated again in the same way “ 946 after 20 [of] Yazdegerd ” and in another part of the first codex (TD²—fol. 218b73x2013;354a) the date is given as “ 978 Pārsāk after 20 Yazdegerd ”. Another date of the same type is, according to the same editor, to be found in another part of the same codex (fol. 203a–20ba), which date relates to the time of the composition of the treaty and reads: “ in the year 357 twenty after Yazdegerd.” The conclusion is that the real name of the era was Pārsāk, that it was expressed by the words “ 20 years after Yazdegerd ” written after the Magian date, which meant that the beginning of the era was twenty years after the era of Yazdegerd, and that the latter became the exclusive means of dating, with the Zoroastrians, only in the last few centuries, and at any rate after the sixteenth century.]

^{page 922 note 1} According to the tradition related by Ibn Isfandiyār, Gāv-bāreh’s independent reign in Ṭabaristān began in the year 35 of “ the new era instituted by Persians ”. This is no doubt the Magian era and the said year began in A.D. 686 (3rd June). For the period between that year and the year 60 of the same era including two reigns, namely Gāv -bāreh and Dāboē our knowledge is limited to the chronicles. From the reign of the third Ispahbed, the great Farruḵẖhan, on, the coins came to the help of the historical records. According to these trustworthy witnesses Farruḵẖān reigned at least from 60 till the year 79 (beg. 23rd May, A.D. 730). His successor Dāḏẖhburzmihr (or Dātburjmatūn) reigned from 79 to 88 (or perhaps to 89) and the last prince ḵẖurshīd from at least 89 till 110. The greatest and most famous of them being Farruḵẖān, his name became to some extent a common name for the Ispahbeds of that province, and not only some of his immediate predecessors are designated by that name by the historians, but also it is given to much earlier chiefs of the province since 639 or A.H. 18 (see Ṭabāri, i, 2659, and Ibn Isfandiyār passim).

^{page 922 note 1} Dīnawarī (op. cit., p. 149) states that the era of the Persian (i.e. Zoroastrians) by which they date “ at the present day ” (third century A.H.) was from Yazdegerd’s death. Bar-Hebraeus in his above-mentioned Syriac book on astronomy published and translated by F. Nau {Le livre de ’ascension de l’esprit …), p. 176 of the French translation, also interprets the era of Yazdegerd as that which is reckoned from the death of that monarch, but in the examples which he gives of the correspondence of the dates of the different eras he counts it unconsciously from the accession of Yazdegerd, i.e. 632.