This example above, of typical composition with two contra-rotating cylinders, two Leyden jars and a hand crack mechanism, has a label for the London optical and scientific instrument maker Dollond and Company of Ludgate Hill.
It stands 17in (42cm) high on a hardwood base.
Offered for sale at Trevanion & Dean (20% buyer’s premium) in Whitchurch, Shropshire, on March 14, it took £2400.