Culpeper style microscope with rack and pinion focusing, c. 1800
This Culpeper type
microscope is unsigned and dates within the first quarter of the 19th
century. Microscopes such as this are derived from the
instruments of the earlier century made by Edmund
Culpeper (1670-1737) and his contemporaries.
These small brass Culpeper style microscopes are
relatively common. They were made for the trade and
consequently, they are often not marked by the retailer or maker.
The microscope is stored
in a pyramidal shaped case with lock and key and is
mounted on a round brass base that supports three
scrolled legs that in turn support the stage. The
mirror is attached on a boss in the base. The circular
stage has a central aperture for illumination by
transmitted light. Three additional scrolled supports
rise from the stage to carry the main tube. Focusing is
achieved by rack and pinion moving the body tube. The optics consist of a double eye-lens and field lens within the body. The objectives are not achromatic. Among
the surviving accessories, which are stored in a lower draw of the case, are four numbered objectives,
a stage forceps, a hand forceps, a sub-stage light
cone, a Bonnani spring stage, an ivory talc box, a fish
plate, and a collection of four ivory sliders each
containing multiple specimens.