In Ruling Engine Work, as it is called, the fine line is present,
also. The engraving is produced and transferred in the same way as the
geometrical lathe work. In this they are parallel and not in circles.
Those which constitute the shading of letters are so fine that they
form a perfectly even gray shade. They may be printed so that the
shading will appear darker, but the aspect will be uniform. The spaces
between lines are exact, whether the lines be horizontal or diagonal.
The lines are also made crooked or wave-like, not absolutely parallel.
Ruling engine work is generally used for shading of names of banks,
and also for the names of town, state, etc.