Page:Philosophical Transactions - Volume 001.djvu/254

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2. That with the same Glass he observ'd Febr. \scriptstyle \frac {14}{24} the Evening, in the other Face of this Planet, two other Spots, like those of the first, but bigger,

3. That afterwards continuing the Observations, he found the Spots of these two Faces to turn by little and little from East to West, and to return at last to the same situation, wherein he had seen them first.

4. That S. Campani, having alto observ'd at Rome with Glasses of 50. Palmes or about 35 Foot, likewise of his own contrivance, had seen in the same Planet the same Phenomena.

4.That sometimes he hath seen, during the same night, the two Faces of Mars, one, in the Evening, tl1e other in the Morning.

6. That the Motion of these Spots in the inferior part of the apparent Hemisphere of Mars, is made from East to West, as that of all the other Celestial Bodies, and is perform'd by Parallels, that decline much from the Equator and little from the Ecliptick.

7. That the Spots return the next day to the same situation, 4O. minuts later, than the day before; so that in every 36. or 37. daies, about the same hour, they come again to the same place.

8. He promises shortly to give us the particular Tables of this Motion and of its Inequalities, together with the Ephemerides themselves.

9. He represents, that some other Astronomers have also made at Rome several Observations of these Spots of Mars, from March \scriptstyle \frac {14}{24}. to March \scriptstyle \frac {20}{30} with Glasses, wrought by Eustachio Divini, of 25. and 45. Palmes: Which Spots he makes little differing from his own, of the first Face; as will by and by appear, by the direction to the Schemes,

10. But he adds, that those other Roman Astronomers, that have observ'd with Divini's Glasses, will have the Conversion of Mars to be performed, not in 24 h, 40 m. (as he maintains it is). but in about 13 h.

11. And to evince, that they are mistaken in these Observations of theirs; he alledges, That they assure that the Spots, which they have seen in this Planet, (by an Eustachian Telescope) the \scriptstyle \frac {20}{30} March, were small, very distant from one another, remote from the middle of the Disk, and the Oriental Spot was less, than the Occidental (as is represented by the Fig. O; like that of the first Face of Mars) whereas, on the contrary,