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illuminated disc turned towards the Earth ; this planet is 5° 
south of the Sun : Jupiter is 9° east, Mercury 25° east, and 
Saturn 30° east of the Sun. 
A Paper was also read by Mr. Thomas Carrick “ On 
the Moon’s Orbit Plane.” 
In previous communications the Author has endeavoured 
to establish a law “ that in all systems of cosmical bodies, 
the equator plane of the primary is the normal of the orbit 
planes of its satellites.” 
To this law the Moon’s orbit presents the only known 
exception. 
The Author pointed out several respects in which the 
Moon differs from all other satellites, dwelling especially upon 
the fact that its gravitation towards the Sun is 2*27 times 
greater than its gravitation tow'ards the Earth ; — a very 
anomalous position for a satellite of the Earth. 
Close analogies were shown to exist between the system 
of the Earth and Moon and the sidereal systems of revolving 
double stars. 
The abnormal position of the Moon’s orbit plane was 
traced to the action of the preponderant gravitation of the 
Sun, and this cause w'as also held to be fatal to the hypothesis 
of the ellipsoidal figure of the Moon. 
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