Mytton Antiques - Jerrard Nares has dated this piece to the 1750s.
The dial held behind a hinged glazed door.

The body with exposed tube, finished to the bottom with a domed cistern cover.
The whole with good boxwood and ebony chequer stringing.
The dial engraved for the maker, P.Ronchoron, Wigan.
Circa 1780
Length 39 inches, width 5 1/4 inches, depth 3 inches.
Mytton Antiques - Jerrard Nares has dated this piece to the 1750s.
Fine antiques from the 18th century onwards, supplying both trade and private customers worldwide.
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