Jeckyll & Co has dated this piece to the 1910s.

Good condition throughout with hand-worked gros-point tapestry seats
Further Reading: Lindsay Macbeth 'The Wheelers of Arncroach. A Family of Furniture Makers, Regional Furniture, 1991 Volume V. A Clam shell chair is illustrated on p73, figure 9
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Jeckyll & Co has dated this piece to the 1910s.
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