Iron eyepiece cap (red outline left) is crudely made and corroded. At its base is a ring of hardened yellow substance (way or amber). Presumably it retained the eyepiece lens (missing).
Field lens at the end of the drawtube is held in place with a metal retaining ring.
Microscope body (length = 11cm)
A: Objective lens (dia=11mm, f=3mm)
B:Field lens (dia=25mm, f=50mm)
C: Eyepiece lens is missing
The objective lens assembly is made from turned wood. The biconvex objective lens sits in a depression in the base. Note the small aperture dia (3mm) compared to the size of the lens.