Spectroscopic Microscope Eyepiece with Bull's-eye Lens, Diagram and Case, by John Browning, London, Early 20th Century

Spectroscopic Microscope Eyepiece with Bull's-eye Lens, Diagram and Case, by John Browning, London, Early 20th Century. The spectroscopic microscope eyepiece has a copper alloy barrel with an eyepiece at one end, which unscrews and is open at the other end. It has a focus knob, a pull ½ slit, a slit fine adjustment and a side slit, a L.H. mask and a side prism mask. It is accompanied by a separate eyepiece with a diagonally-placed lens in a diamond-shaped hole and four rigid protruding twisted wire loops

There is also a bull's-eye lens on a pin with a ball at one end with a screw attachment.

A diagram drawn and written in blue ink and titled BECK SPECTROSCOPIC EYEPIECE" shows the controls on a pentagonal sheet of light blue paper.

The case is a wooden box with a hinged lid and a locking mechanism. It has compartments to hold the objects in place, a deep green plush lining and a separate shallow wooden tray, also with a deep green plush lining.