An introduction to astronomy: designed as a text-book for the use of students in college. By Denison Olmsted ...

2 6'THIE EARTH.
seasons of the year; the periceci have the same seasons, but
opposite hours; and the antipodes have both opposite hours
and opposite seasons.
7 3. To rectify the globefor the sun's place: On the wooden
horizon, find the day of the month, and against it is given the
sun's place in the ecliptic, expressed by signs and degrees.*
Look for the same sign and degree on the ecliptic, bring that
point to the meridian, and set the hour index to XII. To all
places under the meridian it will then be noon.
Ex. Rectify the globe for the sun's place on the ist of September.
74. The atitude of the place being liven, to find the time of
the sun's rising and setting onr any given day at that place:
Having rectified the globe for the latitude (Art. 66), bring the
sun's place in the ecliptic to the graduated edge of the meridian,
and set the hour index to XII; then turn the globe so as to
bring the sun to the eastern and then to the western horizon,
and the hour index will show the times of rising and setting
respectively.
Ex. At what time will the sun rise and set at New Haven,
Lat. 41~ 18', on the 10th of July?
PROBLEMS ON THE CELESTIAL GLOBE.
7 5. To find the Declination and Rnight Ascension of a hieavenly boly: Bring the place of the body (whether the sun or a
star) to the meridian. Then the degree and minute standing
over it will show its declination, and the point of the equinoctial under the meridian will give its right ascension. It will
be remarked, that the declination and right ascension are found
in the same manner as latitude and longitude on the terrestrial
globe. Right ascension is expressed either in degrees or in
hours; both being reckoned from the vernal equinox (Art. 37).
Ex. What is the declination and right ascension of the bright
star Lyra?-also of the sun on the 5th of June?
* The larger globes have the day of the month marked against the corresponding sign on the ecliptic itself.