A fine 18th Century 'Screw-barrel' microscope, unsigned, with lacquered brass body, screw barrel, sprung stage, with turned ivory handle, lens holder, brass cased lieberkuhn, six brass numbered and graduated objectives with turned ivory covers (one missing), black/white opaque holder with screw pin, brass weight holder and forceps, four-segment brass wet cell, four ivory slides, in red velvet-lined fitted mahogany case - 6in. wide