Misura della Base Trigonometrica eseguita sulla Via Appia per ordine del Governo Pontificio nel 1854-55

Rome: Tipografia della Rev. Camera Apostolica, 1858. 1st Edition. Hardcover. Very Good. 1st Edition. Hardcover. 4to - over 9¾ - 12" tall. Folio (327 x 220 mm). [6], 197 [1] pp. Half-title, title with woodcut device, engraved frontispiece and 5 (3 folding) engraved plates. Pages uncut. Bound in fine 20th-century red morocco over xylographic paper boards (slight rubbing to extremities). Light dust-soiling to outer margins, minor browning and occasional minor foxing, remnant of removed green paper wrapper at inner margin of half-title and final plate verso. Very good copy. Provenance: Giancarlo Beltrame Library. ----

FIRST EDITION of Angelo Secchi's report of the exact survey of the Via Appia supervised by him. Between 1854 and 1855 the Via Appia Antica was measured from the monument of Cecilia Metella in Rome to the tower of the locality of Frattocchie inMarino, resulting in a 12,043.14 m long geodesic base. The geodesic operation along Via Appia was born from a double necessity: firstly, to verify the base measured in 1751 along the same road by the Jesuit fathers Ruggiero Boscovich and Christopher Maire - a measure whose correctness had been criticized by French military engineers between 1809 and 1810 - and, secondly, to obtain a new reference value for the drawing of the cartography of the Papal State and of southern Italy. The geodetic base is the side which the geodetic triangulation of a region refers to (direct and very precise measurement of angles between defined points of the territory) and whose length results from a direct measurement on the ground with an error required to be less than a millimeter. With trigonometric formulas, it is possible to subsequently calculate the length of all the other sides also taking into account the curvature of the earth's surface. (See also, T. Aebischer, Padre Secchi geodeta: 1854/1855 e 1870, Astronomia, 3, maggio-giugno 2011, pp. 42-49). - Visit our website to see more images!