From the Aloe & Hernstein Illustrated Catalog:

STUDENT'S MICROSCOPE-Jappanded cast iron foot, with brass pillars which support the axis thus allowing the body to be inclined to any angle; brass arm; coarse adjustment by rack and pinion; fine adjustment by our new patent frictionless motion. Plain and concave mirrors hanging to a swinging bar so as to allow the most oblique light for high powers, and so that the distance from the object may be varied; sub-stage in which the revolving diaphragm or other accessories may be fitted; two eyepeices, viz: A and C, two objectives viz ; 3/4-inch and 1/5-and the latter of 108 degrees angular aperture, resolving easily  P. Angulatum by central light; magnifying powers from 50 to 375 diameters. Eye-piece micrometer, camera lucida. In an upright Walnut case, with handle, lock and key, draw for accessories..................................................................$60

Gundlach Patent  Oct. 3, 1876

Bausch and Lomb Optical Company's Fitting for Neutral Tint Camera Lucida.- Fig. 163 shows the fitting adopted by the Bausch and Lomb Optical Co. It is made of vulcanite, and the half ring to which the frame holding the neutral tint glass is fixed fits on the cap of the eye-piece. The vulcanite is sufficiently elastic to obtain a good grip of the eye-piece.

The microsocpe was designed and made by Ernst Gundlach while employed by Bausch & Lomb.

This microscope was the property of Arthur Claassen (1859-1920), who was well-known as a successful choral and orchestral conductor. It was purchased from his granddaughter for this collection.