Srb a Štys Praha


Measuring Microscope

By Dushan Grujich, on August 25th. 2013

Srb-a-Štys optical and mechanical works was founded in Praha - Prague, in 1919. Srb-a-Štys were producing many optical instruments, microscopes, drafting tools, optical measuring tools for geodesy, astronomy and meteorology as well as military optical sights (telescopes, periscopes and binoculars) .

Company was founded by Jaroslav Srb (1892-1967), which by 1937 had grown to have 860 employees. The fast growing enterprise was abruptly ended in 1939 by Nazi occupation of Czechoslovakia.

After defeat of the Nazi Germany and after the end of WWII, what remained of Srb-a-Štys company was nationalised by Communists and then in 1948 renamed to become known as Meopta.

Measuring microscope № 4761, shown below, is an example of Srb-a-Štys production during the short period lasting from 1919 till 1939 which Czechoslovakia enjoyed as free country.

This measuring microscope came into my possession as part of the lot of surplus equipment discarded from one of the forensics laboratories.


Microscope is made of solid brass, it magnifies 24X and has a cross hair in the eyepiece, used to determine starting and ending points while measuring length using  high precision micrometer, from 0 to 25 mm, with 1 µm precision.
Micrometer thumbwheel has scale with 1/100 mm divisions with vernier allowing readings down to 1/1000 mm i.e. one micrometer.
The base cross bar can be removed for mounting a cross slide or some other accessory for easier and more precise manipulation of the object being measured. 
In order to use the 'scope as was originally intended, not having any of the original accessories, I have mounted a spare cross slide, part of one, of the Boley & Leinen watchmaker's lathe, onto the microscope cross bar.
Typical view, of the non inverted image, as seen through the eyepiece  of Srb a Štys measuring microscope, with 6 mm field of view.

The image shows a balance staff, 337/100 mm long, enlarged 24X, the elements of which are being measured along the X-axis.

Second image shows 'scope used to measure the size of the pallet stone without removing it from fork. 

Using a simple  protractor, one can measure the impulse face angle off the computer screen.