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the Moon's Excentricity.
4. But that Distance Z, seen from the Center of [[underline]] Mars [[/underline]], must have subtended an Angle smaller that Z, in the proportion, nearly, of the Radius, to the Sine of the Angle made at the Center of the Earth, by the Sines drawn from thence to the Centers of the Moon and [[underline]] Mars [[/underline]]. And so their arises a proportionable Uncertainty or [[underline]] Parallax [[/underline]] in the apparent Place of the Center of [[underline]] Mars [[/underline]], as seen from the Center of the Earth, and from G the common Center of Gravity of the Earth and of the Moon: Which Point G describes the Great Orb. And that Uncertainty might amount on one Side of [[underline]] Mars [[/underline]] to the whole Number Z, and to as much on the other Side; if the Moon were in or near her Quadrature with [[underline]] Mars [[/underline]].
5. And therefore, if those two Great Astronomers will be pleased to renew their Calculations upon this Foot, and will have a due Regard to their own Latitude, and to the Hours of the Night/or to the Hours of the Day, if they will hereafter find the Parallax of [[underline]] Venus [[/underline]]; for she may be observed in the Day-time:) They may derive from these their Observations the Situation of G the common Center of Gravity of the Moon and of the Earth, and verify that my Theory is wholly consistent with their Observations. But as long as the Situation of the Center G is unknown, or neglected by them; their Conclusions about the Parallax of [[underline]] Mars [[/underline]], and of the Sun, are most probably greatly erroneous. And so I appeal from their former Conclusions to themselves; or to any Astronomers who, knowing the Circumstances wherein those Observations are or were made, will try my Theory by them. But at the same Time let