Page:Philosophical Transactions - Volume 004.djvu/225

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In this Occultation, as in the preceding, the Center of the Moon passes very near the Star, so that we may well hereby define, as was advertised in the last Occultation, both of her Diameter, and of the places and æquations of her Nodes. For in this, at 12 h. 23 m. 42. sec. P. M. the mean Node was in Aries 19 d. 19 m. 34. sec. and the æquation of the Node to be added, 26 m. 52 sec. which makes the true Node Aries 19 d. 46 m. 26 sec. But in that of March 2 at 16 h. 39 m. 52 sec. the mean Node was in Aries 23 d. 39 m. 33 sec. the æquation was 55 m. 59 sec. to be subtracted; so the true Node was in Aries 22 d. 43 m. 34 sec. Now if this Æquation of the Nodes should be neglected, it might make about 5 min. difference of the Latitudes, which I have here collected. The Ingenuous therefore will observe with all possible accuracy, both under what spots of the Moon the Stars shall enter and emerge in these and all other Occultations; and they will note the Times exactly, considering the benefit, that will thence accrue to Astronomy. The Observers must not content themselves with the timesacquired by Clocks or rectified Watches, but also take the Altitudes of some fixt Star, free from Refraction, and remov'd from the Meridian both at the beginning and end of the Occultations, with exact Instruments of Brass well divided.

So for this diligent Author for this time. The other particulars, contained in his Papers, may perhaps be publisht hereafter. We were to reserve a part of this Tract for some other Communications.

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