Epact Scientific Instruments of Medieval and Renaissance Europe

The second face of the instrument is marked with a double circle divided into eight sectors each marked with the initial two letters of the wind directions, North being placed in the apex of the instrument. Above the north indication is a well modelled head (?olus?) chiselled in relief. The circles and initial letters of Tramontanus are engraved on a hinged flap, attached at the base of the head, which covers a small pin gnomon scaphe dial for Italian hours marked with undivided hours 9 to 23. Below this dial is a partly inset compass (lacks needle and glass), and at the south point a second subsidiary bowl perhaps for a needle locking device. The free space in the corners of the quadrant and beneath the scaphe dial are filled with partly cross-hatched scrolled foliate decoration. Two engraved and moulded sights one with pinnule are set along the longer edge. The plumb and cursors line are missing. The original box has a six roll frame around the edge enclosing a central symmetrical leaf motif, single elements of this being repeated in the corners beneath a five petal flower.

Provenance: Pope Gregory XIII and thence to the Medici collections being mentioned in the Wardrobe Inventory of Ferdinand I (Inv. Guard. Med. N. 190 car 39) as 'Quadrante d'ottone dorato ordinario con oriuolo italiano che era di Papa Gregorio in custodia di corame' and in the 1654 inventory of the Uffizi as 'Un quadrante di ottone dorato, di semidiametro di P. 3, che da una parte vi ? un oriuolo orizzontale con la sua bussola e dall'altra un oriuolo a Sole con il perpendicolo quale manca e che ? fatto all'altewwa di 42, dentro custodia di corame rosso, foderata di velluto simile'.