The title of the book “Logometron architecturae militaris Freitagianae” , written by Andreas Alexander in 1665, is in Latin. This contrasts with the rest of the work, the subtitle and the original language, which are written in Old High German. From the title and the subtitle, which reads “Kunstmass der Freitagischen Bevestigung / Mit gnugsamer Erklärung des Gebrauchs und zugehörigen Theilungs-Tafeln auszgefertiget”, it can be inferred that this is a work about fortress construction, but also about architecture and building, mathematics and military.
The book has no list of contents, but it does have a “Vorbericht”, which sets the mood for the following text. It is about the history of the circle sector. After an introduction to the history of the circle sector I think the author describes the scales and tables of the instrument and what measurements it can perform. A few arithmetical problems follow. He then quickly introduces more complex problems involving military fortifications, geometry, and surveying.
Since the work is a mathematical manual, it has no illustrations, but it does have many geometric sketches.
I think the work can be described as a small paperback as it is a very small size at 10cm x 15cm and not much bigger than the palm of your hand. Because of its size, the book should have been useful to the builders of fortresses to be able to look up something directly on the spot. Another indication that the book was intended for everyday use is that the cover is very simple and not opulently designed. Another possibility would be a schoolbook, as it is divided into tasks and has many explanatory “Tafeln” and geometric drawings in the appendix.