Brightness of the Satellites of Jupiter. 
335 
Brightness and Diameter distinguished. 
July 2 6, 1794. i7 h 14' 41". 10-feet reflector; power 170. 
The 4th satellite is very dim. It is of a pale, dusky, reddish 
colour. 
The 2d satellite is of a bright, white colour. 
The 3d satellite is very bright, and white. 
The 1st satellite is very brilliant, and white. 
i7 h 22' 41". The Magnitudes with 240. 
The 3d satellite is*the largest. 
The 2d satellite is the smallest. 
With 300. 
The 4th satellite is a very little larger than the 2d, though 
less bright. 
The 1st satellite is larger than either the 4th or 2d, 
With 400, the order of the magnitudes is 3 1 4 2. 
With the same power, the order of the light is 3 1 2 4. 
Now and then it appeared to me doubtful whether the 4th 
satellite was larger than the 2d ; and as their light is of an 
unequal intensity, it is difficult without much attention, to be 
decisive about the magnitudes. 
Diameter of the second Satellite by entering on the Disc of 
the Planet. 
July 28, 1794. 17 11 25' 40". 10-feet reflector; power 170. 
The 2d satellite is nearly in contact with the following limb 
of Jupiter, 
