Salusbury, Thomas Mathematical collections and translations 1667

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269
seen in that same note observed the star in the polar altitude of 55
degrees and 58 mi. pri. And the polar altitude of the Landgrave
was 51 degrees and 18 mi. pri. The altitude of the star in the Me­
ridian taken by Tycho was 27 degrees 45 mi. pri. The Land­
grave found its altitude 23 degrees 3 mi. pri. The which altitudes
are these noted here, as you see.

This done, substract the lesse from the greater, and there remains
these differences here underneath.

Where the difference of the poles altitudes 4 gr. 4 mi. pr.
is lesse than the difference of the altitudes of the Star 4 gr. 42 mi.
pr. and therefore we have the difference of parallaxes, 0 gr. 2 mi.
pri. These things being found, take the Authours own figure
[Fig. 2.] in which the point B is the station of the Landgrave,
D the station of Tycho, C the place of the star, A the centre
of the Earth, A B E the vertical line of the Landgrave, A D F



of Tycho, and the angle B C D the difference of Parallaxes. And