Della Specola Astronomica de’ Regi Studi di Palermo…

Palermo: Reale Stamperia, 1792.

First edition, very rare, of Piazzi’s account of the Palermo Observatory, which he established, and where he made the observations that led to his discovery, on January 1, 1801, of the minor planet Ceres. Specola Astronomica includes Piazzi’s description of the astronomical instruments he had commissioned and assembled for the Palermo Observatory, the most famous of which was Jesse Ramsden’s vertical circle, illustrated on the plates in the first volume. A “large theodolite-type instrument was the 5-foot vertical circle which Ramsden made for Piazzi’s new observatory at Palermo. Both Ramsden and Piazzi worked at this instrument, twice abandoned before its completion in August, 1789. The horizontal circle gave readings in azimuth read by a micrometer microscope, and the vertical, readings in altitude by two diametrically opposed microscopes. The divisions on the circles were illuminated by an inclined silver mirror fixed to each microscope, and the wires in the telescope eyepiece by transmitting light from a small instrument through the hollow tube-axis – two Ramsden innovations. This instrument, the finest complete circle hitherto made, formed the basis of Piazzi’s astronomical work. With it he catalogued nearly 8000 stars, compiled a valuable table of refractions, and attempted to measure the parallax of several bright stars. The great labour involved in the catalogue is the more remarkable when we consider that each star was observed several times before its position was decided” (King, History of the Telescope, pp. 166-8, with the circle illustrated). “Palermo was then the southernmost European observatory, and the favourable climatic conditions that it provided allowed him to study more stars than had been previously catalogued, with a greater degree of accuracy” (DSB). Only one other copy has appeared at auction since 1968, and that lacked four preliminary leaves.

“Gioacchino Giuseppe Maria Ubaldo Nicolò Piazzi was born in Ponte, Valtellina, July 16, 1746, to one of the wealthiest families of the region. The penultimate of 10 sons, most of whom died as children, his parents worried about his health and for this reason quickly baptized him at home. The register of baptisms of St. Maurizio Church clearly specifies ‘ob imminens vitae periculum,’ or ‘because of impending danger of death’. Following the tradition that encouraged younger children of wealthy and noble families to take holy orders, Giuseppe joined the Teatine order at the age of 19. We do not have first hand documents about his early studies, but we know from documents preserved in the Archive of the Palermo Observatory that between 1770 and 1780 he was requested by his superiors to teach philosophy and mathematics in many different Italian cities, including Rome, Genoa, and Ravenna. In 1781, he was appointed to the Chair of Mathematics in the newly established Accademia dei Regi Studi of Palermo (which became the University of Palermo in 1806); a few years later, in 1787, he was named to the Chair of Astronomy even though he was not yet even an amateur astronomer. In a matter of only a few years, however, he was to become one of the most respected astronomers of his time.

“In March 1787, soon after he was charged with over-seeing the construction of a new observatory at Palermo, Piazzi departed for a three-year stay at the major astronomical centers of Paris and London. During his travels he gained the esteem and friendship of some of the most reputed astronomers of the time, including Lalande, Messier, Mechain, Cassini, Maskelyne, and Herschel. Moreover, he succeeded in securing for the new observatory a unique instrument: the famous 5-foot circular-scale altazimuth telescope made by Jesse Ramsden of London. Returning to Palermo in November 1789, Piazzi was able, in a matter of months, to have the new observatory built on top of the tower of Santa Ninfa at the Royal Palace” (Serio et al., pp. 17-18).

The Palermo Circle by Jesse Ramsden (1730–1800), the greatest of the eighteenth-century instrument makers, was completed in 1789 after almost two years of intense work. The telescope has a 7.5-cm objective lens; the altitude scale (5 feet in diameter) was read with the aid of two diametrically opposed micrometer microscopes while the azimuth scale (3 feet in diameter) was read by means of a micrometer microscope.

“Encouraged by the possession of the 5-foot Palermo Circle, whose accuracy was regarded to be much superior to that of any other existing instrument, Piazzi centered his scientific program on the accurate measurements of stellar positions. His observational technique required that each star had to be observed for at least four nights before its position could be established. This painstaking work resulted in the publication in 1803 of his first star catalog. For this highly regarded work, he was awarded the prize for mathematics and physics at the Institut National de France, Fondation Lalande, and was elected a fellow of the Royal Society. It was while working on this catalog that Piazzi, on January 1, 1801, unexpectedly discovered Ceres, the ‘missing planet’ between the orbits of Mars and Jupiter” (ibid.).

Piazzi published two additional parts of this work, but without plates, in 1794 and 1806 (the last part is exceptionally rare).

Lalande, p. 622 (“Ce grand et précieux ouvrage”). Serio, Manura & Sicoli, Giuseppe Piazzi and the discovery of Ceres (

Folio (370 x 255 mm), pp. xxxii, 240 and 4 folding engraved plates (the first plate showing Ramsden’s vertical circle measures 650 x 470 mm). Uncut and completely untouched in the original carta rustica, a very fine, fresh, and crisp copy.

Item #3288

Price: $4,800.00