304 GEOGRAPHY AND ASTRONOMY. of the sun's apparent continuance in different signs of the zodiac : He seems to tarry longer in those of the summer, and shorter in those of the winter: So that he does not leave one sign, and enter another just in the same proportions or distancesof time every month. 7. This occasions a little variation of the declination of the sun, and his right ascension from the regularity that we might expect for they are both derived from his apparent place in the ecliptic : And therefore none of them can be found by learners with utmost exactness, but in an ephemeris or tables which spew the sun's place, &c. every day in the year. 8. Let it be noted also, that the leap-year with its additional day the 29th of February, returning every four years, forbids the sun's place in the ecliptic to be exactly the same at the same day and hour of the following year, as it was in the foregoing ; so that though you knew the sun's place, his right ascension and declination for one whole year, that would not serve exactly for the next year, for the nicest purposes of astronomy. 9. Yet as in four years time the sun appears very nearly at the same place in the heavens again at the same day and hour and minute as before, so a table that contains the round of four years is a sufficient direction for 20 years to find the sun's place for any common purposes : Provided always that we seek the sun's place, declination or right ascension, for any year and day in that year in the table that is equally distant from leap-year whether it happens to be the first, the second, or the third after leap-year, or whether it be the leap-year, itself. See more ofthis matter, Sect. XXI. of the Tables of Declination. I0. If we would make one single table or scale of the sun's entrance into the signs of the zodiac, or of his declination or right ascension to serve for everyyear, we must chuse the second after the leap-year, because that comes nearest to the tnean or middle course and placeof the sun, and will occasion the least error in any operations. t have therefore here set down a short table of the sun's entrance into the several signs, for the year 1754, which is the second after leap-year ; and for geometrical operations with a plain scale and compass, it is sufficiently exact for 20 years to come. Anno 1754, the second after leap-year. Day d. m. Day m. d. .March 20T-0 : 09 Sept. 23 =-0 : 21 April 20 -0 : 19 Oct. 23 tiff, -0 : 3 May 21-11-0 : 16 Nov. 22y0 : 14 June 22 -25-0 : 51 Dec. 22VS-0 : 44 July 23-9..---0 : 25 Jan. 21w 0 : 33 4-ugust 23-11R -0 : 11 Feb. 20 x0 : 55
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