The following is the result of an impartial discussion of this very interesting subject. The reasoning of the "spirit" is false. The system of Uranus is almost perpendicular to the plane of its orbit. It is the direct opposite of that of the satellites of Jupiter, which turn almost in the plane of their orbit. The inclination of the plane of the satellites to the ecliptic is 98°, and the planet ascends almost in the plane of the ecliptic. This is a fundamental consideration in the picture which we ought to make to ourselves of the aspect of this system seen from the earth.
Let us, however, adopt for the method of movement of these satellites around their planet the projection upon the plane of the ecliptic, as has always been the custom. The author maintains that, "when the north pole of Uranus is turned toward the earth, his satellites run their course from right to left, that is to say from west to east"; he indorses the communication of the spirit to the effect that the astronomers are in error and that the satellites of Uranus really revolve around their planet from west to east, in the same way that the moon revolves around the earth.
In order to give ourselves an exact account of the position and of the method of the movements of this system, let us construct a special geometrical figure, clear and precise. Let us represent upon a plane the appearance of the orbit of Uranus and of its satellites seen from the northern hemisphere of the celestial sphere (Fig. A). The part of the orbit of the satellites above the plane of the orbit of Uranus has been drawn with heavy lines and hatching, the lower part in dotted lines only.
It is easily seen by the direction of the arrows that the revolution of the satellites, projected upon the plane of the orbit, is entirely retrograde. All dogmatic affirmations to the contrary are absolutely erroneous.
These satellites turn like the hands of a watch,--from left to right, looking at the upper part of the circles.
The error of General Drayson's medium comes from the fact that she maintained that the south pole of Uranus was turned toward us at the date of its discovery. Now, in 1781, the system of Uranus occupied relatively to us almost the same situation as in 1862, since the time of its revolution is eighty-four years. It is evident from the figure that, at that moment, the planet presented to us the pole most elevated above the ecliptic; that is, its north pole.