Instruments of the Restored Astronomy

EXPLANATION OF THE CONSTRUCTION AND USE.

Its use is uniform with the previous instrument in all those matters which are to be observed through Altitudes and AzimuthsThe horizontal direction of a celestial body, measured as an angle around the horizon. and demonstrated geometrically, and from there resolved into numbers. It should be known, nevertheless, that these two Quadrants are not to be trusted too much when an extremely exact observation down to a small fraction of a minute is required. Such observations are those which serve the restoration of the Sun’s course original: Solaris curriculi, where the matter concerns the smallest details and requires a precision of a sixth, or at the very least a third part of one minute; this, such small instruments—which span only one or one and a half cubits A cubit is an ancient unit of length, roughly the distance from the elbow to the tip of the middle finger.—cannot provide. Therefore, let us now turn to larger instruments more suitable for such tasks. These will facilitate not only this subtlety required regarding the Sun, but also the investigation of the tiniest ParallaxesThe apparent displacement of an object when viewed from different points; used by astronomers to determine the distance of celestial bodies. and their differences (if there be any) in any celestial phenomenon. Furthermore, they will reveal many other things most scrupulously in observations of both the wandering stars Planets and the fixed stars.

Those eager for such matters will find examples of these parallaxes in the second volume of our Introductory Exercises for the Restoration of Astronomy original: Progymnasmatum nostrorum Astronomiæ instaurandæ. There, in both the first and second parts, I deal diligently with seven comets observed within the past twenty years, and I scrutinize their parallaxes as subtly as they could be obtained. I demonstrate geometrically and infallibly that they all existed in the Aethereal Region far above the Moon; even though there is no shortage of those among them who,