Page:Philosophical Transactions - Volume 001.djvu/309

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Digits, by casting the Figure through a 5 foot Telescope, on an extended paper, fix't at a certain distance from the Eye-glasse, and having a round figure; all whose Diameters were divided, by 6 Concentrick Circles, into 12 Digits.

THe Observations made at Madrid by a Noble Member of the Royal Society, His Excellence the Earle of Sandwich, as they were sent to the Right Honourable, the Lord Vice Count Brounker, are these;

The Eclipse began at Madrid about 5 of the Clock in the morning, at 35′. the Suns Altitude was 6 deg. 55′.

The Middle of it was at 6 h. 2′; the Suns Altitude, 15. deg. 5′.

The End was exactly at 7 h. 5′; the Suns Altitude, 25. deg. 24′.

The Duration, 2 h. 4′.

37. Parts of the Suns diameter remained light.

63. Parts of the same were darkened.

The Observations made at Paris by Monsieur Payen, assisted by several Astronomers, as they were printed in French, and addressed to Monsieur de Montmar are these;

The Ecplise began there, at 5 h. 44′. 52″. mane. It ended at 7 h. 43′. 6″. So that is Whole duration was 1h 58′. 14″. The greatest Obscuration they assign to have been 7. dig. 50. m. but they adde, that it seem'd to have been greater by 3 minuts, which M. Payen imputes to a particular motion of Libration of the Suns Globe, which entertain'd that Luminary in the same Phasis for the space of 8. min. and some seconds, as if it had been stopped in the midst of its Course; rather than to a tremulous Motion of the Atmosphere, as Scheiner would have it.

They intimate that they took the time of each Phasis from half digit to half digit, as well by a Pendulum, as by the Attitudes of the Suns Center above the Horizon, corrected by the Verticall Paralaxes of the Æstivall Refractions, by which they judged, that though the Time by the Pendulum, may be sufficient for Mechanicall Operations, yet 'tis not exact enough for establishing the Grounds of true Astonomy.

They further conceive that the apparent Diameters were almost equal; seeing that in the Phasis of 6. Digits, the Cirucumference of the Moons disk passed through the Center of that of the Sun, so as that two Lines drawn through the two Horns of the Sun, made with the Common Semi-diameter two Equilateral Triangles.

Next, they affirm, That there was so great a Variation in the Parallaxes, by reason as well of the Refractions of the Air, which environs the Earth, as of the Alteration of the Air, which encompasses the Moon, that the Horns of the Sun, there formed by the Shaddow of the Moon, appeared in all kinds of Figures; Sometimes inclined to the Vertical, sometimes Perpendicular

to the Horizon, and at last Parallel; the Convex part respecting the Heaven, and the Concave, the Horizon, By the crossing (so they go on) of the

Horns