Beschreibung:

A superb example of a very rare type of binocular telescope, signed and dated PETRVS PATRONVS SAC: CÆSÆ. ET CATÆ. MAIESIS. OPTICVS MEDIOLANI. 1720 (Petro Patroni of the Holy Catholic Roman Empire, Optician of Milan 1720), the outer, rectangular body tube made of pasteboard and covered in embossed black leather, the draw-tube of vellum dyed green and decorated with gold tooling, the signature and date also gold tooled into the vellum, both ends with silver mounts, with hinged covers providing access to the optical tubes, the eye end with a pair of silver shutters opening out to act as blinkers to assist clear vision, one engraved with a monogram, the other with arms, closing over a painted surface with apertures in the shape of an eye with painted eyebrows, below the apertures the words VISIO and PERFECTA ; at the exterior of the objective end the lenses are protected by apertures incorporating silver slides, above the apertures the painted words AGIT IN PVNCTO and between them two forearms, each hand grasping a pair of compasses. The objective lenses are in ebony mounts on vellum-covered tubes, 2¼in. (5.6cm.) long , the lenses .13/16in. (2.1cm.) diameter , the aperture ½in. (1.2cm.) diameter . Both lenses are signed round their edges with a diamond Petrvs Patronvs Medio or Milano . The lenses are held in position by a slip of wood stuck in position, making the last word hard to read. The outside of the mounts are labelled in silver paint C D . The eyepieces are of the erecting form, each with three biconvex lenses, held by ebony and ivory mounts on vellum tubes 56in. (13.2cm.) long overall . The mounts are identified in silver paint by the letters A B and the same on the tubes in ink. At either end the interocular distance can be adjusted by using a watch key to turn a left/right screw that effects the movement of a pantograph that displaces the tubes to suit the eyes of the observer. The separation is recorded by small silver watch dials, numbered in roman I-XII . When closed the telescope packs into a box 16.1/8 x 5.15/16 x 3.1/8in. (41 x 15 x 8cm.) covered in brown leather with gold tooling round the edges, lined in -- 14.7/8in. (37.8cm.) long overall closed; 4¾ x 2¼in. (12 x 5.8cm.) cross-section See Front Cover and Details