Description

Exquisite 4 section walnut and brass compass in 4 quadrants (N, E, S, O) with 360 degree outer ring in one degree divisions with 3 magnetic declinations. The 4 inch compass needle points North and locks via a large butterfly nut to a brass bar below the jewelled pivot point. The smaller butterfly key allows for correction of magnetic North. There are two additional clock type keys that fit this square head as well.

6 inches square and 1 inch thick (15 x 2.5 cm.), the compass frame has a wonderful round knurled ring to the reverse terminating in an articulating 3 inch stem with butterfly nut to accomodate a tripod or staff for field surveying.

The Everest pattern simple theodolite/transit consists of double “wings” that read from 70-170 degrees on the left side and 30-130 degrees on the right, with worm and screw verniers (0-50) that allow for accuracy to one arc minute. The wings articulate from and central pivot point allowing for connection to the 7 x 3/4 inch telescope (wonderful optics with cross hairs intact-draw tube focussing). The telescope is surmounted by a green glass bubble level with fluid intact. The sighting tube can be angled (+/- 30 degrees) by knurled screw mounted perpendicular to the vernier screw. A marvelous piece of engineering that does away with the telescope being surmounted above the compass as with the T&S pattern Everest transit theodolites of the era (post 1830). By inclining/declining the telescope it eliminates 60 degrees from the arc circle and hence reduces cost of the instrument. Everest claimed (with the help of Simms) this would cut costs by 4X.

The wooden compass frame is flawless as is the original golden lacquer of the instrument (including the compass dial). The main screw controlling tension of the theodolite to the compass frame has been over tightened and bruised at one point in time. Everything works as intended  with fabulous precision. Museum quality.