Anodized brass sextant with oval-pattern frame, polished limb and wooden arm in fitted mahogany box, made by William Heath, Plymouth, England, 1850-1880. Consists of inlaid polished silver 130° scale (-5° to 153°) with 10’ divisions, silver vernier (10”), four filter shades (red & green) and three horizon filters (red & green), scale magnifier on swivelling arm (lens missing). Fitted with threaded telescope bracket for sighting telescopes (87mm - star finder, 85mm – erect image, 189mm – inverted image & 82mm – sighting tube).