The illustration below was found in the drawer of the storage case. Note the alternate placement of the fine adjustment knob:

There is evidence that this microscope and similar microscopes signed by other makers (such as James W. Queen, Philadelphia) were actually made by Samuel Murset of Philadelphia. J. G. Langguth Jr. was an importer and dealer in optical goods located at 117 Randolph St, and later at 88 State St. in Chicago. Samuel Murset was a Swiss immigrant scientific instrument maker who worked at 86 North 7th St. and later at 9 North 11th St. in Philadelphia. Here are photos of a very similar microscope made entirely of brass. It is signed "Saml. Murset, Philada" on the stage.