This example being understood, it will be easy to find when either of the other two superior Planets, _viz. Mars_ and _Saturn_, rise, set, and come to the meridian. I shall conclude this subject about the Globes with the following problems. PROB. XLVI. _To find all that space upon the Earth, where an Eclipse of one of the Satellites of_ Jupiter _will be visible._ Having found that place upon the Earth, in which the Sun is vertical at the time of the eclipse, by _Prob. 13_, elevate the globe according to the latitude of the said place; then bring the place to the meridian, and set the hour index to 12 at noon. If _Jupiter_ be in consequence of the Sun, draw a line with black lead, or the like, along the Eastern side of the horizon, which line, will pass over all those places where the Sun is setting at that time; then count the difference betwixt the right ascension of the Sun, and that of _Jupiter_, and turn the globe Westward, ’till the hour index points to this difference; then keep the globe from turning round its axis, and elevate the meridian, according to the declination of _Jupiter_. The globe being in this position, draw a line along the Eastern side of the horizon; then the space between this line, and the line before drawn, will comprehend all those places of the Earth where _Jupiter_ will be visible, from the setting of the Sun, to the setting of _Jupiter_. But if _Jupiter_ be in antecedence of the Sun (_i. e._ rises before him) having brought the place where the Sun is vertical, to the zenith, and put the hour index to 12 at noon, draw a line on the Western side of the horizon; then elevate the globe according to the declination of _Jupiter_, and turn it about Eastward, until the index points to so many hours distant from noon, as is the difference of right ascension of the Sun and _Jupiter_. The globe being in this position, draw a line along the Western side of the horizon; then the space contained between this line, and the other last drawn, will comprehend all those places upon the Earth where the Eclipse is visible, between the rising of the Sun, and that of _Jupiter_. [Illustration] _The_ DESCRIPTION _of the Great_ ORRERY, _lately made by Mr._ THOMAS WRIGHT, Mathematical Instrument-Maker to his late MAJESTY, and now by BENJAMIN COLE, _his Successor_. The ORRERY is an Astronomical Machine, made to represent the motions of the Planets. These machines are made of various sizes, some having more Planets than others; but I shall here confine myself to the description of that above-mentioned. In the Introduction we gave a short account of the _Order_, _Periods_, _Distances_, and _Magnitudes_ of the _Primary Planets_; and of the _Distances_ and _Periodical Resolutions_ of the _Secondary Planets_ round their respective Primaries. We shall here explain their _Stations_, _Regradations_, _Eclipses_, _Phases_, _&c._ but first let us take a general view of the _Orrery_.