INTRODUCTION
The Siddhanta-darpa14 of Nilalkartha Somayāji (born 1443) critically edited here with his own commentary, is a short but important work of this moted astronomer of Kerala, which enunciates the basic astronomical constants as verified and adopted by him. . It also sets forth certain other matters including the theory of epicycles as understood in Hindu astronomy. The textual verses with translation had been issued by the present writer, more than twenty years ago, through the pages of the well-known Indological journal, the 4८yar Library Bulleti1, 19 (1955) 327-68. The special significance of the present edition consists in its being embellished with the elaborate commentary on the text by the author himself .
Manuscript material
The edition presented in the following pages is based on seve1 manuscripts of the text, designated A to G, one of the manuscripts containing the commentary as well, all inscribed in the Malayalam script on palmleaf.
A. Ms. No. 475-D of the Kerala University Oriental Research Institute and Manuscripts Library, Trivandrum. It is an old and reliable Imanuscript found in a codex of more than a dozen astronomical works. The codex is dated sey0 dugdhabdhitalpa, wiट., the 16,99,847th। day of the Kali era, which works out to A.D. 1551, just a few years after the death of the author in about A.D. 1545
B. Ms. 5867-C of the above Library. The manuscript carries a comparatively pure text, and is included in a codex of several ] astronomical works. A moder1 paper transcript of this manuscript in Devanagari script is available in the Madras Government Oriental Mss Library, No. R. 5151 (b)
C. Ms. No. (C. 1869-C of the Curator's Collection of the Kerala University Mss. Library. This manuscript is much injured and the । rect0s of the folios are broken.away. The beginning of the manuscript is lost and the work is available only from verse 13.
D. Ms. No. (C. 1024-F of the Curator's Collection of the above Library. This is a well preserved manuscript found in a codex of
vii
