Although this essay from a much younger Rene Schwaller, it none-the-less provides hours of contemplation on the metaphysical meaning of numbers. His ideas on numbers as they relate to cycles of (on-going)creation are rooted in a scientific background. He even goes so far as to demonstrate his ideas in a practical example of salt-crystal formation. If it weren't for the content involved, the book could be read in one evening as it is a slim volume. However, it IS philosophical and not casual reading by any stretch of the imagination. A book for anyone interested in the metaphysical side of numbers, sacred architecture, numerology and even the aspects of the Tarot may be better understood from this essay.
As noted by the translators, one of whom is Robert Lawlor, Schwaller left emphatic instructions about how this work was to republished in accordance with his later studies on the Egyptian mysteries. Without going into great detail this book should probably be read after at least reading The Temple of Man by Schwaller.
The Theology of Arithmetic by Iamblichus, Robin Waterfield (trans.) provides an excellent foundation to the Study of Numbers by Schwaller. Actually this text or one like it might've been Schwaller's inspiration in this study.