A rare Breguet instrument set, by Negretti & Zambra., Hatton Garden, London, circa 1890, a portable barometer with two mercury tubes and pieces for assembly housed in a silk lined wooden case, the brass base plate marked Negretti & Zambra, Hatton Garden, London and numbered 2274-I-1886, original tubes also with maker's marks, the case 5 cm high, 38.5 cm wide, 12 cm deep