on the singular Figure of the Planet Saturn. 277 
with the four corners rounded off so as to leave both the 
equatorial and polar regions flatter than 'they would be in a 
regular spheroidical figure. 
The planet Jupiter being by this time got up to a consi- 
derable altitude, I viewed it alternately with Saturn in the 10- 
feet reflector, with a power of 500. The outlines of the figure 
of Saturn are as described in the observation of the 4,0-feet 
telescope ; but those of Jupiter are such as to give a greater 
curvature both to the polar and equatorial regions than takes 
place at the poles or equator of Saturn which are compara- 
tively much flatter. 
May 12. I viewed Saturn and Jupiter alternately with my 
large 10-feet telescope of 24 inches aperture; and saw plainly 
that the former planet differs much in figure from the latter. 
The temperature of the air is so changeable that no large 
mirror can act well. 
May 13. 10-feet reflector, power 360. The shadows of the 
ring upon the body, and of the body upon the ring, are very 
black, and not of the dusky colour of the heavens about the 
planet, or of the space between the ring and planet, and be- 
tween the two rings. The north-following part of the ring, 
close to the planet, is as it were cut off by the shadow of the 
body ; and the shadow of the ring lies south of it, but close to 
the projection of the ring. 
The planet is of the form described in the observation of the 
40-feet telescope ; I see it so distinctly that there can be no 
doubt of it. By the appearance, I should think the points of 
the greatest curvature not to be so far north as 45 degrees. 
The evening being very calm and clear, I took a measure- 
