Page:Philosophical Transactions - Volume 001.djvu/257

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times as big, as the Diameter of the Moon appears to the naked Eye. I saw the Limb pretty round, and very well defin'd without radiation. The parts of the Phasis of it had various degrees of Light. About a and f, the North and South poles of it (in the Fig. Q) 'twas somewhat darker, and by degrees it grew brighter towards b. and e, two Belts or Zones; the one of which (b) was a small dark Belt crossing the Body Southward; Adjoyning to which was a smal Line of a somewhat lighter part; and below that again, Southwards, was the great black Belt c. Between that, and e, the other smaller black Belt, was a pretty large and bright Zone but the middle d, was somewhat darker than the edges. I perceiv'd, about 3h 15m near the middle of this, a very dark round Spot, like that represented at g, which was not to be perceiv'd about half an hour before: And I observed it, in about 10. minutes time to be gotten almost to d, keeping equal distance from the Satelles h, which moved also Westwardly, and was joyn'd to the Disk at i, at 3h 25m. After which, the Air growing very hazy, and (as appeared by the Baroscope) very light also (in weight) I could not observe it: So that it was sufficiently evident, that this black Spot was nothing else, save the shadow of the Satelles h, Eclipsing a part of the Face of Jupiter. About two hours before, I had observed a large darker spot in the bigger Belt about k, which in about an hour or little more (for I did not exactly observe the time, nor draw the Figure of it) moving Westwards, disappear'd. About a week before, I discover'd also, together with a Spot in the Belt c. another Spot in the Belt e, which kept the same way and velocity with that of the Belt c. The other three Satellites in the time of this Eclipse, made by the Satelles, were Westwards of the Body of Jupiter; appearing as bright through the Tube, as the Body of Jupiter did to the naked Eye, and I was able to see them longer through the Tube, after the day-light came on, than I was able to see the Body of Jupiter with my naked eye.

A late Observation about Saturn made by the same.

Figure R
Figure R

June 29 1666. between 11. and 12. at night I observed the Body of Saturn through a 60. foot Telescope, and found it ex-

actly