Card-Mica covered with paper, blue with blue and black markings, graduated to 1/4 points and quadrantally in degrees.
Needle- Six light edge bar needles composed of one thin strip of steel with the ends bevelled of sharply, 2 x 7", 2 x 5.25" and 2 x 6.25" long, and 0.25" deep. The two inner needles 2" apart and the rest 1" apart. Attached to a light metal ring which is screwed to card.
Pivot-Missing, screwed through centre of light framework which has two short arms secured to the inner needles and two long arms attached to the metal ring of card, in the N-S direction, these carrying sliding weights.