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NAUTICAL  DICTIONARY.
 

head of a ship when a tiller cannot be used.'    (Seamanship, by
Lieut. Nares, ^g, 1.)

YOU-YOU. A small Chinese boat impelled with the scull,
used on rivers and in well-protected harbours and roadsteads.
The Chinese are a people who make the most especial use of the
scull in rowing, sometimes eight or ten men working at one scull.
(Diet, de Marine a voiles.)

ZENITH. In Astronomy, the zenith of any place on the
globe is *that point in the heavens immediately above the place,
and the nadir is that point immediately under it. Hence the
zenith and nadir are the poles of the rational horizon,' from
which at every point they are distant 90°.    See Circles.

The Zenith Distance of a celestial object is an arc of a
vertical circle contained between the centre of the object and the
zenith: if the object be on the meridian, it is termed meridian
zenith distance. (Norie's Epitome; Paper's Practice of Navi¬
gation and Nautical Astronomy.)

ZODIAC, in Astronomy, a space including about 8|-° on each
side of the ecliptic, within which the motions of all the planets
are performed.    (Baharie's Marine Board Examination.)

The ecliptic or zodiac is divided by astronomers into twelve
equal parts, called signs of the zodiac, each containing 30°. They
are thus named: —
 

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1.  Aries (the Earn).

2.  Taurus (the Bull).

3.  Gemini (the Twins).

4.  Cancer (the Crab).

5.  Leo (the Lion).

6.  Virgo (the Virgin).

7.  Libra (the Balance).
 

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8.  Scorpio (the Scorpion).

9.  Sagittarius (the Arrow-bearer or

Archer).

10.  Capricornus (the He-goat).

11.  Aquarius (the Water-bearer).

12.  Pisces (the Eishes).
 

The first six signs, being on the north side of the equinoctial,
are termed northern signs; the last six, being on the south side of
it, southern signs.

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