Jason Clarke Antiques has dated this piece to the 1800s.
In differentiation from the normal bi-convex lens this has a huge eight inch convex-concave or meniscus lens retained against the body by means of a circular mahogany slip fitted on top of the lens after it has been inserted into the one piece body.

An unusual but effective method of construction which gives the piece a rather “looking glass” aesthetic
One of the largest of its type that I have handled measuring ten inches in diameter and with the unusual construction and lens combination, a really interesting variation. The lens remains in fantastic condition.
A very imposing magnifier which would have been used in either a library or gallery setting to allow closer visual inspection.
Jason Clarke Antiques has dated this piece to the 1800s.
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