4It was only after Italian Unity (1860) that a "modern" geographical survey of Sicily was accomplished. The need for such a survey was deeply felt at the turn of the eighteen century, by the reformist party. Reliable cadastral data were in fact needed, if only for taxation purposes. On Piazzi's efforts and failure to produce such a map see: G. Foderà Serio and L. Indorato, The Matthew Berge's instruments at the Palermo Astronomical 0bservatory, Annali dell'Istituto e Museo di Storia della Scienza di Firenze, VI, 1981, pp. 217-24; G. Foderè Serio and P. Nastasi, Giuseppe Piazzi's survey of Sicily: the chronicle of a dream, Vistas in Astronomy, vol. 28, 1985, pp. 269-276.