226 GEOGRAPHY AND ASTRONOMY. Libra, -Scorpio, Sagittarius, are 'descending signs, for their suc- cession tends lower toward our horizon, or rather toward the southern hemisphere. Each of these signs has 30 degrees of the ecliptic allotted to it. 'I'he sun or any planet is said to be in such a sign when he is between our eye and that sign, or when he appears in that part of the heavens where those stars are of which the sign is composed. If it be enquired, how we can know the place of the sun among the stars, since all the stars near it are lost in the sun- beams ? It is answered, that we can see' plainly what constel- lation or what stars are upon the meridian at midnight, and we know the stars which are exactly opposite to them, and these must he upon the meridian (very nearly) the same day at noon; and thereby we know that the sun at noon is in the midst of them. So that when you have a globe at hand on which the stars are delineated, you find on what degree of any sign the sun is in on a given day, and see the stars around it. The sun is reckoned to go through almost one sign every month or thirty days, and thus to finish the pear in 365 days 5 hours and 49 minutes, i. e. near 6 hours : So that the sun may be supposed to move slowly as a snail through almost one degree of the ecliptic line every day from the west to the east, while it is whirled round together with the whole frame of the heavens from east to west, in a line parallel to the equator in the time of 24 hours. Note, We vulgarly call the sun's diurnal, or daily path a parallel to the equator though properly it is a spiral line, which the sun is ever making all the year long, gaining one degree on the ecliptic daily. From what has been now said it appears plainly, that the equinoctial line, or equator itself, is the diurnal path of the sun about the 20th or 21st of March and the 23d of September, which are the two opposite points where the ecliptic, or yearly path of the sun, cuts the equator. And these two days are called the equinoctial days ; when the sun rises and sets at six o'clock all the world over, (i. e. where it rises and setsat all that day ;) and the day and night are every where of equal length; and indeed this is the true reason why this line is called the equator or the equinoctial. It may not be improper in this place to remark that those 5 hours and 49 minutes, which the sun's annual revolution re- quires above 365 days, will in 4 years time amount to near a whole day. Therefore every fourth year has 366 days in it, and is called the Leap-year.--Note, The super-added day in that year is the 29th of February in Great- Britain. It may be W- ilier remarked also, that the odd 11 minutes which in this account
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