The text in Schüblers Synopsis architecturae civilis eclecticae is written in very compact text blocks with a small margin in between the two pages and bigger margins towards all other directions. The font has the typical old German style and the letters are quite small, just big enough to read without problems if you’re familiar with old German letters.
All paragraphs are numbered in the middle of the page. Together with the chapter titles, this is the only time the block of text gets interrupted.
Illustrations of Schüblers perspective drawings of details and bigger architectonic elements are scattered throughout the book, always taking up a full page and also leaving the reverse empty, because the print presses through the paper quite heavily. There is exactly one chapter per illustration (or the other way around). The drawing is almost always located at the end of the corresponding chapter.
The pages are numbered, but all illustrated pages and their backside are left out of the numbering. I can imagine that in previous published versions, the illustrations were separate of the text, maybe even two physical books. This would make sense not only because of the faulty numbering but it would also be much more convenient to look at the drawing while reading about it without having to turn pages every couple of seconds.
The illustration pages have a separate numbering corresponding with the chapter (e.g. Tab. IX – Tab is short for Tabelle, or translated: chart). There are two more levels of numbering for details inside those charts: Parts of drawings are titled Fig. 52 as an example. Single reference points in the drawing are named with capital letters. This makes referencing in the text more clear.
Roman numbers are only used for chapters and their charts. For pages, paragraphs and the drawing details Schübler uses Arabic numerals to avoid confusion.