Bowl- Copper with a lead balancing weight at base, inside of bowl painted white. four lubberlines are fitted, consisting of copper strips with a line cut in each. The glazed verge ring, dia. 11.25" (28.6cm) is fitted with an azimuth sight consisting of a short fixed vane with a sighting aperture and a long folding arm which has a deep line cut on its inner surface. A thread runs from the base of the folding vane across the bowl, up through the aperture of the fixed vane and secures to a tightening screw at the upper end of the folding vane. The verge ring is fixed and the whole bowl has to be turned to take bearings. Four pillars on the verge ring also carry a thread; purpose unknown. Attached by pivot points to black painted brass brackets which are secured to wooden stand. Dims. 15" x 6.75" x 1.25" (38.1cm x 17.1cm x 3.2cm)
Card- Diameter 8.5" (21.6cm) Mica, covered with white paper, graduated around edge quadrantally in degrees and the eight principal are hand-painted N, S, O, W and coloured red and black. NO, SO, SW, NW are black and blue. Has five blobs of sealing on the underside for balancing.
Needle- Flat bar-type 8.5" (21.4cm) long. Secured by two screws to underside of card. Pivot cup screwed through centre of needle.
Pivot- Brass stem screwed to bottom of bowl carries a brass pivot point which engages in cone-shaped pivot cap, whcih has jewel at top, attached to nedle and centre of card.