I get it. There's a lot of holes. A lot of columns. It will all make sense, I promise. The Ames Lettering Guide is a drafting tool that is used to create evenly spaced parallel lines. It's a great tool for calligraphers to use when creating guidelines for projects.
Purchase the Ames Lettering Guide at: https://www.paperinkarts.com/amesgu.html (It's only $4!)