Paper Instruments in the History of Ottoman Astronomy

Gaye Danişan Polat from the Department of the History of Science, Istanbul University provides us with an overview of her research which has been funded by a grant from the SIS. Full details to follow in a subsequent issue of the Bulletin.

The importance of using paper instruments during the Ottoman period remains unexplained because there are few surving examples to help us understand their role in the history of Ottoman astronomy. To date there are still several important questions that need to be answered: When were paper instruments first used by Ottoman astronomers? Which style of paper instruments were used? Who used them? Were they widely used across the Ottoman world? Were the paper instruments used for education or actual calculations?

This study aims to clarify the purpose of using paper instruments in the Ottoman world by assessing the following surviving examples in the astronomical literature: the first example is a calendar with the title of Ruzname-i Şeyh Vefa (replicated by Ibrahim Shahidi ibn Khoudaï Dede in 1676, BnF supplément turc 537). It includes a paper instrument with two moving circles (volvelles) representing the positions of the Sun and Moon (folio 6). Composed of a series of concentric circles, this instrument enabled the user to perform calculations relating to the age and phase of the Moon, lunar mansions and eclipses (both solar and lunar). The second example (Fig. 1, below) is also a calendar in the Kandilli Observatory (MS 540, copied A.H.1134/1721-22 A.D) made of cardboard by Derviş Mehmed el-Hasib el-Mevlevi (d.1709) who was a muwaqqit (timekeeper). There is a gurrename on the top right corner, and also circles & semicircles featuring the names of planets, zodiac signs, fixed stars, and information about the climates, zodiac, and winds.

The third example (Fig. 2) is an Ottoman book on navigation entitled Navigasyon (1857) which features a serko haritası which is equivalent to a quartier de reduction (sinical quadrant) used among French mariners. We can assume that this printed paper instrument was used for pedagogical purposes since the Navigasyon was written for students at the Naval School (Mekteb-i Bahriye). Finally, there are also a few examples mounted on wood that can be to use as surviving instrument like cylindrical sundial, qıblanuma, quadrant. This project will contribute to our understanding of the use and role of paper instruments within the history of Ottoman astronomy.

Note: For more detailed information about serko haritası in the Ottoman Empire see: Danışan Polat G., “Osmanlı Denizcileri ve Serko Haritası (Quartier de réduction)”, in: Osmanlı Bilimi Araştırmaları/Studies in Ottoman Science, XVIII/1 (2016), pp. 1-25.