Origin of the ruling pen

We have passed weeks looking for the origin of the ruling pen, and it has been impossible to find the year in which the first ruling pen was used (its invention), so, what we have done is look for things that have gone before (which is nothing, as the ruling pen was the first tool with the usage of drawing lines...) and instruments that have gone after: quill, rotring art pen...

So, the instrument that came just after the ruling pen was the quill, that was invented in the year 1827 which means that the ruling pen appeared before the year before mentioned.

In the Middle Ages, the printing house was invented, so we think that between the Middle Ages and the Renaissance, the need of tracing accurate lines with ink of different widths, maybe to write or something similar.

So, we have got to the conclusion that between the Middle  Ages and the Renaissance, the ruling pen was invented.