Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/296

 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 Meridian taken by Tycho was 27 degrees 45 mi. pri. The Landgrave found its altitude 23 degrees 3 mi. pri. The which altitudes are these noted here, as you see.

''gr. m.	 	gr. m.'' Tycho. Pole	55	58	*	27	45 Landgr. Pole	51	18	*	23	3

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

''gr. m.'' 4	40 	4	42 Parall. 2

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, ABE the vertical line of the Landgrave, ADF

of Tycho, and the angle BCD the difference of Parallaxes. And