The title page is the only page in English. The entire rest of the book is gibberish as pictured here.

The bookstore had placed it near member volumes from early American fraternal orders. America had, at one time, a number of social organizations modeled after European secret societies that slowly faded as America became more urban: the Freemasons, Odd Fellows, Order of the Eastern Star or Knights of Columbus, for example. However, this little book doesn't fit with the orders' general goals of mutual self-help and community building.

After months of staring at it, one day, it just made sense. It's not gibberish, it's English. A partial translation of the displayed page is here.

We can only speculate as to what the author's point was in producing this, but the best guess is it's pseudo-mystic, the idea being, "If you can read it, then you were meant to."

A (turn of the century word for surface) is a figure of two dimensions, namely length and breadth.

A solid is a figure of three dimensions, namely length, breadth and thickness.

By this science, the architect is enabled to construct his plans and exact his designs, the general to arrange his soldiers, the engineer to make out ground for encampments, the geographer to give us the dimensions of the world, and all things therein contained; to delineate the extent of seas, and specify the divisions of empires, kingdoms and provinces. By it, also, the astronomer is enabled to make his observations, and to fix the durations of times and seasons, years and cycles. In ---, Geometery is the foundation of architecture, and the root of mathematics.

After that, you're on your own. Keep at it and eventually it makes sense. The antiquated word usage is generally the biggest obstacle.