In A Nutshell Antiques and Interiors has dated this piece to the 1920s.
In marine navigation this is used to help determine a ship's position and plot its course.

The instrument is contained within its original good quality wooden box with sliding lid. It has a makers label on the top for"Dobbie McInnes & Clyde Ltd. Marine & Mechanical Makers to the British Admiralty. Glasgow".

It is in good condition for its age. There are some signs of age and use, a few small knocks and marks but nothing detrimental and the folding sight lines open smoothly. The box is sturdy with a lovely patina.

Approximate Measurements :
Diameter : 7 1/2" / 19cm
Box : 8 3/4” / 22cm square x 2" / 5cm high
The best description comes from the photos so please look at them all carefully and if you have any questions just ask.
Tracked UK Delivery £8
In A Nutshell Antiques and Interiors has dated this piece to the 1920s.
Selling good quality victorian, georgian and earlier furniture, accessories & decorative items. Ashburton, devon. LAPADA member
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In A Nutshell Antiques and Interiors is a registered member of LAPADA CINOA