Now if the rest are in general from each other, allowing the same Extent of System, and as much to part the like Extreams of active Virtue, be in such Proportion of aerial Space, it will appear, that to pass from any one Star to another, we must fly thro' so vast a Tract of pure Expanse or Ether, that to visit any one of the most neighbouring Systems, could we travel even as fast as the swiftest Eagle flies, for Instance, 500 Miles per Day, yet should we be 3,000,000 of Years upon our way before we could arrive there; and if continuing on to view the Regions of the rest within the known Creation, Myriads of Ages would be spent, and yet we could not hope to see the whole of but the smallest Constellation.
But what Idea of Distance can you receive from this sort of Estimation, where Numbers arise so very high. I own to you mine are soon quite lost by this Method of counting, either, Distances or Duration. I believe few People can range their Ideas with such Perspicuity, as to arrive at any adequate Notion of any Number above a thousand.
To give you therefore a clearer Idea of Distance, and impress the Proportions of Space more strongly and fully in your Mind, let us suppose the Body of the Sun, as I have said before, to be represented by the Dome of St. Paul's; in such Proportion a spherical Body eighteen Inches Diameter, moving at Mary-le-bone, will justly represent the Earth, and another of five Inches Diameter, describing a Circle of forty-five Feet and a half Radius round it, will represent the Orbit and Globe of the Moon. A Body at the Tower of 9,7 Inches, will represent Mercury; and one of 17,9 Inches at St. James's Palace will represent the Planet Venus; Mars may be supposed at a Distance, like that of Kensington or Greenwich, 10 Inches Diameter: Jupiter, imagined to be at Hampton-Court, or Dartford in Kent; and Saturn, at Cliefden, or near Chelmsford: The first represented by a Globe 15 Foot 4 Inches Diameter, the latter by one of 11 Feet ¾ Inches and his Ring four Feet broad: These would all naturally represent the planetary Bodies of our System in their proper Orbits and proportional Magnitudes, as moving round the Cupola of St. Paul's, as their common Center the Sun. And preserving the same natural Scale, the Aphelion of the first Comet would be about Bury, the second at Bristol, and the third near the City of Edinburgh. But if you will take into your Idea one of the nearest Stars; instead of the Dome of St. Paul's, you must suppose the Sun to be represented by the gilt Ball upon the Top of it, and then will another such upon the Top of St. Peter's at Rome represent one of the nearest Stars.
The whole System exhibited in the above Proportion, would be nearly as follows:
| Diameter of the | Sun | 145 Feet. |
| Saturn | 11,587, his Ring 27,54, its Breadth 4. | |
| Jupiter, | 15,39. | |
| Mars, | 10,15 Inches. | |
| the | Earth, | 18,125. |
| Venus, | 17,98 | |
| Mercury, | 9,715 | |
| and | the Moon, | 4,93 |
| [AU]Distance of | Saturn from the Sun, | 27 Miles, and 1700 Yards. |
| Jupiter, | 15 Miles, and 458 Yards. | |
| Mars, | 4 Miles, and 751 Yards. | |
| the Earth, | 2 Miles, and 1632 Yards. | |
| Venus, | 2 Miles, and 217 Yards. | |
| Mercury, | 1 Mile, and 267 Yards. | |
| and of the Moon, from us, 45 Yards and a half. | ||
[AU] Of the Satellites of Saturn in the above Proportion.
The 1 } would be { 27,96 } Feet distant from his
Center.
2 } { 35,52
3 } { 50,
4 } {114,
5 } {341,9
And those of Jupiter.
The 1 } would be { 28,51 } Feet distant from him.
2 } { 69,177
3 } { 110,224
4 } { 190,