Card-Mica covered with paper, blue with blue and black markings, graduated to 1/4 points and quadrantally in degrees.
Needle- Four very light edge bar needles, composed of one thin strip of steel, 2 x 7.25" and 2 x 5.25" long, and 0.25" deep at edge. The upper edges of the needles are cut away which reduces their depth by half. All attached to a light metal ring which is screwed to card.
Pivot- Cone-shaped pivot cap with jewel at top, screwed through centre of light framework which has two short arms secured to the two inner needles and two long arms attached to the metal ring of card in N-S direction.