Unusual Negretti and Zambra round base microscope, circa 1875 The heavy base marked; NEGRETTI & ZAMBRA 1 HATTON GARDEN LONDON All brass with original lacquer. Focusing on rack and pinion. Single sided concave mirror. One unmarked eyepiece. One unmarked objective in cannister. Stage with screw fixed large blackened brass stage clips. All mechanical motions smooth and functional, all in good working order, with good optics. In clean bright sound used condition noting some wear to the lacquer finish. Mahogany fitted box, brass carrying handle, working lock and key, repaired split to the door. Height of box 8" or 203mm, Gross weight 2.733 kilos