Jason Clarke Antiques has dated this piece to the 1860s.
The lift out tray reveals a further base section containing two unmarked ebonised parallel rules. The velvet within the lid is marked in gilt lettering, “Cary, Optician to the Admiralty, War Office etc etc. 181 Strand, London. To HRH The Prince of Wales, HRH The Duke of Connaught & HRH The Duke of Teck”.

The Cary dynasty were highly regarded instrument makers of the late eighteenth and nineteenth centuries, the two brothers William and John forming a partnership manufacturing both scientific apparatus and globes from their London address. Both founders had passed away by the end of the 1830’s leaving the business to the family. The history is somewhat unclear at this point but it seems that two of the firms employees, Henry Porter and Henry Gould acquired the firm in the early 1860’s at which point the firms output was marked “Gould & Porter (late Cary)”.

Given the use of the Cary name on this set and that it references The Duke of Teck, a revived title bestowed in 1863 on Count Francis Von Hohenstein who later married Princess Mary Adelaide of Cambridge, daughter of the Duke of Cambridge and grand daughter of George III, it allows for accurate dating of the set from 1863 to 1865.
Jason Clarke Antiques has dated this piece to the 1860s.
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