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26. But there is a midling Sort of Orbits and Dichotomys, which deserve our most particular Attention; namely, those that occur, when the Moon, being in her Quadrature, is also in her Apogee or Perigee. For then, the [[underlined]] Section, [[/underlined]] terminating the Light in the Moon's oval Body, and made by a Plane parallel to its longest Axis, may be exactly or nearly directed towards the Observator; and the Parallax of the Sun may be easily deduced from the Observation itself, even as if the Body of the Moon were Spherical. And such an Observation, tho' but a single one, will be without Exception, and altogether decisive. Thus having by it ascertained the Sun's [[underlined]] Parallax [[/underlined]], or else only determined [[underlined]] it[[/underlined]] by our own Methods and Demonstrations; the Case being more simple; we may best, once for all, calculate [[underlined]] a priori [[/underlined]], by Means of that Sort of Orbits, the Proportion of the longest Axis of the Moon to her shorter ones. And that Proportion may likewise be determined, by means of a sufficient Number of promiscuous Observations of Dichotomys.
27. Astronomers have no great Privilege, above any other Persons, to make accurate and decisive Observations of Dichotomys of the Moon. And whereas disinterested Judges of this Controversy can never be too numerous, I desire all sincere Lovers of Truth, who would satisfy themselves, and promote the true Knowledge of the System of the World (wherein Astronomy and Navigation, &c. are so much concerned) to be provided, in any Country whatsoever, with a proper Telescope, easily manageable at a Window, suppose a Telescope of one Foot, or of about [[strikethrough]] of[[/strikethrough]] six or seven or eight Feet, having a very broad ocular Glass, and a proportionable Tube, and in the Focus one Bit, or two or three parallel Bits of [[stretch?]].[[end of page]]