Do not, however, expect, star-loving reader, that here anything at all that you may wish can be drawn forth as from its source, for to demand this would be almost the same as to seek to drain as from a cup all the vast knowledge of the many arithmetical sciences from the narrow confines of one book. You will understand how impossible that is when, through prolonged labor, you have grown somewhat more mature in this kind of learning.
Wherefore, rather fully, and out of consideration for you, I have decided, setting aside these prolixities, with completely synoptic brevity and with all possible clarity to expound for you simply the proportion of the movements, the description of the machine, and its usage. As a result, when you have progressed a little in theoretical mechanics, you will not only be able to reduce all these things to their astronomical principles, but you may find the way more smoothly laid out for you even for perfecting the machine itself. And, thus, you may be more effectively encouraged to a successful conclusion. Let it be so now for you through the following 10 chapters!
After these rather hopeful assurances, Father Borghesi proceeded to provide a detailed description of the clock dial and functions in the 10 short chapters which he had promised, under a separate section entitled "Synopsis Totius Operis Mechanici," which is translated in its entirety in the appendix.
As Father Borghesi prepared his little volume about his first clock, and described its unusual features and outlined its functions, which were primarily to place in evidence the celestial constellations, it occurred to him that it would now be easier after the experience he had acquired with his first timepiece, to construct another clock, which would present the motions of the two astronomical systems, the Ptolemaic and the Copernican. In this first book, he promised the reader that he would undertake the second project. It is fortunate that Father Borghesi undertook this project for the second clock is the only example of his work that is known to exist today. Extensive research has not shown what happened to the first clock, although several sources state that both timepieces were presented to Empress Maria Theresa sometime between 1764 and 1780.