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which is the star Regulus, of the first magnitude. In summer nights 
the zodiacal constellations Scorpio and Sagittarius are very remarkable 
and beautiful. But perhaps the easiest way to note the position of the 
zodiacal constellations is to watch the progress of the Moon from night 
to night during any lunation. She describes, with sufficient accuracy 
for such purposes as this, the same path as the Sun, and in one thir- 
teenth part of the Sun's period ; so that while the Sun takes about 30 
days to pass from one of the zodiacal constellations to the next, the 
Moon covers the same space in little more than two days. If then the 
Moon's place in the zodiac be known when first she is seen (at the new), 
she will mark out the next constellation of the zodiac (eastwards) in 
about 55 hours from that time. Her brightness, especially at the full, 
makes it difficult to recognize the detail of the constellation in which 
she is situate ; but the constellations east and west of this one may be 
easily and satisfactorily examined. 
Once the observer has made himself well acquainted with the belt 
in the heavens known as the zodiac, he will find no difficulty in assuring 
himself that the Moon is not the only celestial sphere which traverses 
this path. At different hours of the night and at different times of the 
year he will see the planets [upiter, Saturn or Mars as very brilliant 
stars differing only by the steadiness of their light from the other 
bright stars in one or other part of the zodiac. At the present time 
Jupiter is the most brillant star in the sky. and is in the constellation 
Taurus, a little south of the Pleiades. But Jupiter, Saturn and Mars 
may easily be distinguished from the true stars by the fact that they 
change their places with regard to these. It is on this account that 
they are named Planets (wanderers), and it is a peculiarity of their 
movement to which I would specially ask your attention to-night. 
Speaking broadly, any of these planets will be seen to travel over the 
same course as the Moon, that is from west to east, among the zodiacal 
constellations but, of course, with much greater slowness. If we could 
view the Earth's motion in the zodiac from the Sun as our station of 
observation, (and though this cannot be done in fact, it may easily be 
done with the aid of imagination), we should see the Earth complete 
the circle from Virgo, in March, to Leo, in the following February ; in 
