on the Planet Saturn . 
3 
original of which was delineated from nature, on the 20th 
of June, i" 83 , by means of a very good 10-feet reflector. 
It fhould be noticed, that the black dilk, or belt, upon the 
ring of Saturn is not in the middle of its breadth; nor is the 
ring fubdivided by many fuch lines, as has been reprefented 
-in divers treatifes of aftronomy ; but that there is one fin°-ie, 
dark, confiderably broad line, belt, or zone, upon the ring, 
which I have always permanently found in the place where 
my figure reprefeuts it. I give this,, however, only as a view 
of the northern plane .of the ring, as the fituation of the 
planet has hitherto not afforded me any other. The fouthem 
one, which is lately come to be expofed to the fun, will 
fhortly be opened fufficiently to enable me to give a!fo the 
fituation of its belts, if it fhould have anv. 
From my obfervations it appears, that the zone on the 
northern plane of the ring is not, like the belts of Jupiter or thofe 
of Saturn, fubjecl to variations of colour and figure; but is moft 
probably owing to fome permanent conftruCtion of the furface 
of the ring itfelf. That however, for in fiance, this black belt 
cannot be the (hadow of a chain of mountains, may be gathered 
from its being vifible.all round on the ring; for at the ends of 
the anfae tnere could be no (hades vifible, on account of the 
direction of the fun’s illumination, which would be in the line 
of the chain ; and the fame argument will hold good againft 
fuppofed caverns or concavities. It is moreover pretty evident,, 
that this dark zone is contained between two concentric circles, 
as all the phenomena anfwer to the projection of fuch a zone. 
Thus, in fig. 4. which was taken the nth of May, 1780, 
we may fee, that the zone is continued all round the ring, 
with a gradual 4 ecreafe of breadth towards the middle, 
B 2 anfwering 
