SEf'.TION XX, 203 Example June 11th IV7ërid. Alt. Hs 62 Sun's Declin. ES 231 t Colatitude HE 381 -rj tn December 11th Merid. Alt. Hv 15 Sun's Devlin. Ev 231 Colatitude HE 381 Then if you substract the colatitude from the zenith or 90, you find the latitude, as, Zenith Hz 90 Colatitude ne 381 LatitudeEz 511 After all it must be observed here, that all these problems of finding the latitude of the place by the sun or star's meridian altitude, &c. belong chiefly to those places which lie within the temperate zones. If the place lie in the torrid or frigid zones, these methods of solution are good, when the meridian sun is on the same side of the zenith with the equator, whe- ther north or south. But if not, then there must be some little difference of operation at sometimes of the year. Yet if you project a scheme for the solution of such an enquiry like figure an, the very reason of things will shew you when you must add or substract. Problem VIII. 0° To find the meridian altitude of the sun any day of the year, the latitudeof the place being given." This is but the converse of the former problem, and there- fore is to be performed the contraryway, viz. in winter sub- street the declination v E from the equinoctial altitude or colati- tude H E, and the remainder is H v the meridian altitude. In summer add the declination E S to the equinoctial altitude, or colatitude H E, and it gives the meridian altitude H s. Theme- ridian altitude at the equinoxes is the same with the colatitude as before. Problem IX. " To find the declination of the sun, its me- ridian altitude and the latitude of the place being given." It is hardly necessary to describe this practice to those who have perfectly learned the two foregoing problems. Substract the colatitude H E from the meridian altitude T 3
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