تحقيق ما للهند (Al-Biruni's India — Sachau edition, BnF)

This period of time is limited more narrowly by a statement from the author on page 195, line 20, where he notes that the constellation of Ursa Major the Great Bear in his time, specifically in the year 952 of the Śakakâla a Hindu calendar era starting in 78 AD, occupied the space between 1 1/3° Leo and 13 1/2° Virgo. The Śakakâla year 952 corresponds to the period between March 8, 1030, and February 25, 1031, which is the year immediately following the death of Maḥmûd.

A further limitation is found in a passage on page 161, line 9, where the author identifies the year in which he wrote as the year 1340 of the era of Alexander. However, as the year 1030 AD corresponds to the year 1341 of the Seleucid era rather than 1340, this statement requires clarification. Since the beginning of the Seleucid era is October 1, 312 BC, by January 1, 1030 AD, exactly 1340 full years and three months had elapsed. By October 1, 1030, a full 1341 years had passed. If Alberuni wrote after October 1, 1030, he could no longer identify the current year as 1340. Writing before October 1, 1030, he was justified in calling the time in which he wrote 1340, as he was reckoning only complete years and excluding fractions.

Through these considerations, it is established that he composed the Indica between April 30 and September 30, 1030 AD.

It is astounding that in such a short period, Alberuni composed a book of considerable size, characterized by exact research and a polished style. It is reasonable to assume he had written parts of the book previously and simply reproduced them from his earlier publications, such as the theological and philosophical sections See p. f, 20. Likely, he also had astronomical and other tables ready from former studies, particularly those requiring lengthy calculations. We also have reason to suppose he utilized the assistance of very learned scribes.

The summer in which Alberuni wrote (1030) was a stormy time. Everything in the Ghaznavî empire, which then included Persia, the western half of Central Asia, Afghanistan, and parts of India, seemed to be collapsing. As the storm threatened, Alberuni retreated into his study and buried himself in literary work. Once the conflict subsided, he hastened to conclude it. It is tempting to connect this fact with the political events of the time.

Before dying on April 30, 1030, Maḥmûd formally nominated his son Muḥammad, who resided in Balkh, as his successor.