Hence it may be deduced, (by following the method described in a paper formerly read to this Society) that the planet was in opposition January 13a. 04b. 56′ M. T. Greenwich, in longitude, 3a. 23°. 32′. 24″ from the mean equinox, with −°. 30′. 38″ north heliocentric latitude.The error of the theory in longitude is nearly +5″, and in latitude nearly −18″.I attribute this error in latitude to the different manner in which I observed the declinations. I formerly obferved the difference of

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... ference of declination between the planet and fixed star by means of a common micrometer. But I was obliged to substitute Dr Bradley's rhombus for my micrometer, which had received an injury which I could not get repaired in time. If this be allowed, the error in longitude will be diminished nearly 2″.