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CHAP. 6. The Elevation of the Pole and Declination of the Sun given, to find his Amplitude.
THe Amplitude of the Suns rising or setting is an arch of the Horizon intercepted betwixt the Aequator and the place of the rising and set∣ting of the Sun. And it is either Northern or Southward, the Northern Amplitude is when he sets and riseth on this side of the Equator, toward he North Pole: and the Southern when he sets or riseth on the contrary side. Now when the Sun is in the Aequator, he hath no Amplitude at all: but when he is in the Solstitial points, he hath then the greatest Amplitude. That we may find then the Suns amplitude or distance from the East or West points at the time of his rising or setting; let D P L G F represent the Me∣ridian, F A I the Horizon, D A L the Equinoctial. P the Pole of the Aequator.
Then in the Rectangle Spherical Triangle A B C, let there be given the angle B A C or complement of the Poles elevation, 38. 47 and B C the Suns Declination 23. 15. To find A B the Suns Amplitude, The Ana∣logie is.