Historical microscope
The Carl Zeiss Jena microscope with serial number 57684 was delivered to Dr. R. Fritzsche in Schneeberg/Saxony on June 20, 1912.
This type of microscope was introduced in 1898 and considered the technical and ergonomic needs of its users which was unusual until this time. This very early form of user experience (UX) design became the model for countless other microscope stands around the world. For the first time, the control knobs for the coarse and fine drive were axially parallel, so that they could be operated comfortably even when working for long hours.
Whereas typical microscope stands could previously only be moved when the fine drive was loaded during lifting, these microscope stands used a completely new concept: The specially designed "handle" was designed for everyone to carry the microscope intuitively. This characteristic handle gave the popular stand, which was built in a similar way for more than two decades, the nickname "beer mug". Countless scientists from the first quarter of the 20th century had themselves photographed with the ZEISS "beer mug".
A very old German word: pröbeln
In the dictionary, pröbeln means "to make all kinds of (unsuccessful) experiments". Pröbeln was the term for the development of microscope objectives before they could be calculated. Today we would say trial and error. Abbe's formula put an end to "trial and error" in microscope construction in 1872.