Stem with fixed Stage and Lenses for Simple Microscope, English, c. 1755

Stem with fixed stage and lenses. The hexagonal brass stem which screws into the folding flat tripod. A short arm is mounted at the top of the stem by a compass joint, which supports a dovetail limb. The limb is graduated and the stage is held on a sliding sleeve. The stage has an upper ring capable of holding thin sliders and a heavier lower ring on a sprung hinge can hold a tube. Six objective lenses are mounted in a click-stop rotating disc. A hole in the mounting shows which lens is in place. Fine focusing is by a screw that runs though the limb to a mill-edged knob. At the lower end of the limb is a rod on a hinge mounting that could hold a substage mirror. No mirror is present.