Observational evidence and the evolution of Ptolemy's lunar model / Paolo del Santo, Giorgio Strano.
Abstract:
In this article we analyze the classical method introduced by Hipparchus for the determination of the radius of the lunar epicycle based on the observation of triads of eclipses. We also consider the methods and procedures by which Ptolemy was led to the definitive form of his lunar model. Our research suggests the need for new considerations of the origin and significance of the prosneusis, traditionally regarded as a wholly unsatisfactory device, and demonstrates the limits of the traditional historiographical approach to the question
Nuncius A. 11, fasc. 1 (1996), p. 93-122