Superb Heath sextant, ca. 1912, bell frame, box, all access, rare Knorre level

  

Superb Heath "20th Century Mark I" sextant, ca. 1912 (date of certificate), bell frame, box, all accessories, rare Knorre level. This is a very fine example from this major maker in excellent cosmetic, mechanical and optical condition. Mirrors and filters excellent, all optics bright and clear.

Rack and pinion little signs of any wear. Maker's name and location beautifully inscribed on the scale arm. The scales have not been worn as main image shows bleached due to limited dynamic range of camera. The close up of the scales shows no detectable wear at all and no evidence of random micro-scratching of repeated cleaning. The box base has two drying back splits as shown.

Left as-is but readily repaired by a skilled worker if desired. A fine split but no gap on box lid. Recessed brass handle, box opened by the recessed buttons either side. The brass plunger at back of box releases a catch in central pillar to remove the sextant.

This model has the Knorre spirit level with liquid and bubble still intact on the index arm. The small black tube just above the scale magnifier, level viewed from above. This is not a common feature of any sextant model and was named after the Russian astronomer who suggested it for certain land based sightings with an artificial horizon. Thank you to a member of the Facebook Celestial Navigation group for naming and identifying the purpose of this feature.

The silver tube in the accessories image exchanges for the one in the lowest brass tube to provide the option of either parallel lines or cross hatch. A long pin not shown also included. Or can be emailed to potentially interested viewers.