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are wanting yearly to make up a complete day of 24 hours, are accounted for in the new style by leaving out a whole day once in 133 or 134 years. And it is the neglect of accounting for these odd minutes in the old style above a thousand years backwards, that has made the difference between the old style and the new to be at present eleven days.

Note, The zodiac is fancied as a broad belt spreading about 7 or 8 degrees on each side of the ecliptic, so wide as to contain most of those stars that make up the 12 constellations or signs. The inner edge of the wooden horizon is divided into 360 degrees, or 12 times 30, allowing 30 degrees to every sign or constellation, the figures of which are usually drawn there.

The next circle to these on the horizon contains an almanack of the old style which begins the year eleven days later; and the next circle is an almanack of the new style which begins so much. sooner; and these shew in what sign the sun is, and in what degree of that sign he is every day in the year, whether you count by the old style or the new.

Note, One side or edge of the brazen meridian is also divided into 360 degrees or 4 times 90; on the upper semicircle whereof the numbers usually begin to be counted from the equator both ways toward the poles: On the under semicircle they begin to be counted from the poles both ways toward the equator for special uses, as will afterward appear. And it should be remembered that it is this edge of the brass circle, which is graduated or divided into degrees, that is properly the meridian line. The equator and the ecliptic are called unchangeable circles, because wheresoever we travel or change our place on the earth these circles are still the same.

SECT. III. Of the Lesser Circles.

THE lesser circles divide the globe into two unequal parts, and are these four, all parallel to the equator, (viz.) the two tropics, and the two polar circles.

1. The tropic of cancer just touches the north part of the ecliptic, and describes the sun's path for the longest day in summer: It is drawn at 23 degrees distance from the equator toward the north. And it is called the tropic of cancer, because the sun enters into that sign the 21st of June, the longest day in

the year.

*This was contrived to be done by Pope Gregory in the year 1582, in this manner. Since three times 153 years make near 400 years, be ordered the additional day to be omitted at the end of three centuries successively, and to be retained at the 400th year or 4th century. But in this reformation of the calendar he looked back no farther than the Council of Nice. This order almost all foreign nations observed: Great Britain did not observe it till the year 1752, when it was introduced and established by act of parliament,

II. The tropic of capricorn just touches the south part of the ecliptic, and describes the sun's path for the shortest day in the winter: It is drawn at 23 degrees distance from the equator toward the south. And it is call the tropic of capricorn, because the sun enters into that sign the 21st of December, the shortest day in the year. Note, What I speak of the shortest and longest days, relates only to us who dwell on the north side of the globe: Those who dwell on the south side have their longest day when the sun is in capricorn, and their shortest in cancer.

III. and VI. The north and south polar circles are drawn at 23 degrees of distance from each pole, or which is all one, at 90 degrees distance from the contrary tropic; because the inhabitants under the polar circles just lose the sun under the horizon one whole day at their midwinter, or when it is in the utmost part of the contrary side of the ecliptic; and they keep it one whole day or 24 hours above their horizon at their midsummer, or when it is in the nearest part of their side of the ecliptic. The north polar circle is called the arctic circle, and the south is the antarctic.

Here I might mention the five zones by which the ancients divided the earth, for they are a sort of broad circles: But perhaps these may be as well referred to the following part of this book.

SECT. IV. Of the Points.

THE most remarkable points in the heavens are these twelve or fourteen.

I, and II, are the two poles of the earth or heavens, (viz.) the north and the south, which are ever stedfast, and round which the earth or the heavens are supposed to turn daily as the globe does upon these iron poles. These are also the poles of the equator, for they are at 90 degrees distance from it. From one of these poles to the other a supposed line runs through the centre of the globe of earth and heavens, and is called the axis or axle of the world.

III, and IV, are the zenith, or point just over our head; and the nadir or the point just under our feet, which may be properly called the two poles of the horizon, for they are 90 degrees distant from it every way.

V, VI, VII, and VIII, are the four cardinal points of east west north and south: These four points are in the horizon which divide it into four equal parts.

Note, For the uses of navigation, or sailing, each of these quarters of the heavens, east, west, north and south, are subdivied into eight points, which are called rhumbs; so that there are 32 rhumbs or points in the whole, each containing 114 degrees. These are described on the utmost circle of the wooden horizon. From the north towards the east these points are named north and by east, north north-east, north-east and by north, north-east;

north-east, and by east, east-north-east, east and by north, east, &c. Then from the east toward the south it proceeds much in the same manner. The whole circle of 360 degrees divided in this manner is called the mariner's compass, by which they count from what point of the heavens the wind blows, and toward what point of the earth they direct their sailing, which they call steering their course. See figure 11.

IX, and X, are the two solsticial points: These are the beginning of the signs cancer and capricorn in the ecliptic line, where the ecliptic just touches those two tropics. These points shew the sun's place the longest and shortest days, (viz.) the 21st of June and the 21st of December. Note, These two days are called the summer and winter solstices, because the sun seems to stand still, i. e. to make the length of days neither increase nor decrease sensibly for 20 days together.

XI, and XII, are aries and libra, or the two equinoctial points, where the ecliptic cuts the equator: When the sun enters into thse two signs, the days and nights are equal all over the world. It enters aries in spring the 21st of March, which is called the vernal equinox, and libra in Autumn the 23d of September, which is called the autumnal equinox. These four points, (viz.) two equinoctial and two solsticial, divide the ecliptic into the four quarters of the year.

Here let it be noted, that the twelve constellations or signs in the heavens obtained their names about two thousand years ago or more; and at that time the stars that make up aries or the ram, were in the place were the ecliptic ascending cuts the equator; but now the constellation aries is moved upward toward the place of cancer near thirty degrees; and so every constellation is moved forward in the ecliptic from the west toward the east near thirty degrees; so that the constellation or stars that make up the sign pisces are now in the place where aries was, or where the ecliptic cuts the equator in the spring: And the constellation virgo is now where libra was, or where the ecliptic cuts the equator in autumn. So gemini is in the summer solstice where cancer was; and sagittarias in the winter solstice where capricorn was: And by this means the sun is got into the equinoxes in pisces and virgo, and is arrived at the solstices in gemini and sagittarius, i. e. when it is among

those stars.

This alteration is called the procession of the equinox, i. e. of the equinoctial signs or stars, which seem to be gone forward, i. e. from west to east; but some call it the retrocession of the equinox, i. e. of the two equinoctial points, which seem to be gone backwards, i. e. from east to west. This comes to pass by some small variation of the situation of the axis of the earth with regard to the axis of the ecliptic, round which it moves by a coni

cal motion*, and advances 50 seconds or almost a minute of a degree every year, which amounts to one whole degree in 72 years, and will fulfil a complete revolution in 25,920 years. This period some have called the platonical year, when some of the ancients fancied all things should return into the same state in which they now are.

Yet we call these equinoctial and solsticial points in the heaven, and all the parts of the ecliptic by the same ancient names still in astronomy, and mark them still with the same characters viz. Y, 8, II, 5, S, &c. though the constellations themselves seem to be removed so much forward.

XIII, and XIV. Here it may not be improper in the last place to mention the poles of the ecliptic which are two other points marked generally in the celestial globe.

If there were an axis thrust though the centre of the globe just at right angles with the plane of the ecliptic, its ends or poles would be found in the two polar circles. So that a quarter of a circle or 90 degrees numbered directly or perpendicularly from the ecliptic line shew the poles of the ecliptic, and fix these two points through which the two polar circles are drawn.

It is usual also in books of this kind to mention two great circles called colures, drawn sometimes on the celestial globe through the poles of the world, one of which cutting the ecliptic in the two solsticial points is called the solsticial colure; the other cutting it in the equinoctial points is called the equinoctial colure, but they are not of much use for any common purposes or practices that relate to the globe.

I think it may not be amiss before we proceed farther, to let the learner see a representation of all the foregoing circles and points on the globe, just as they stand in our horizon at London, and so far as they can be represented on a flat surface, and in strait lines.

Let the north pole be raised above the north part of the hori zon 51 degrees which are numbered on the brazen meridian, then let the globe be placed at such a distance as to make the convexity insensible, and appear as a flat or plain surface, and let the eye of the spectator be just level and opposite to c. which represents the east point of the horizon: then the globe and the circles on it will appear nearly as represented in Figure 11.

The large circle divided by every 5 degrees represents the meridian, the rest of the larger and the lesser circles are there

*The axis of the earth is supposed to be fastened at its middle in the centre, while both ends of it, or each of the roles in this motion describes a circle round each pole of the ecliptic, which is the base of the cone. The vertexes of each of these cones meet in the centre of the earth; and by this motion of the earth, all the fixt stars seem to be moved from their former places in circles parallel to the ecliptic.

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