Jeckyll & Co has dated this piece to the 18th Century.
Structurally sound.
There is a patch, made of laburnum at the back of the chair where it joins the seat, and a similar smaller patch on the other side of the chair. Laburnum, while decorative, is also notoriously difficult to work with, and these patches appear to be contemporary with the chair's making. Measures 43cm from the floor to the top of the seat.

It is interesting to note the similarites with this model and chairs designed by Sir Robert Lorimer and Whytock and Reid more than a century later.
Please let me know if you require further images and a more detailed report.
Further reading: Scottish Vernacular Furniture by Bernard D. Cotton, publish by T & H, pp158-159 plates 264 and 265.
Jeckyll & Co has dated this piece to the 18th Century.
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