C 48 3 
VIII, On the Rotation of the Planet Saturn upon its Axis. By 
William Herschel, LL. D. F. R. S. 
Read January 23, 1 794. 
In a late paper on the multiplicity of the regular belts of the 
planet Saturn, I pointed out an analogy, which might lead us 
to surmise that it had a pretty quick rotation upon its axis ; I 
can at present announce the reality of that rotation. The 
following series of observations, in which Saturn has been 
traced through one hundred and fifty-four revolutions of its 
equator, will sufficiently confirm it. 
The changes in the belts of Jupiter, it is well known, are so 
frequent, that we find some difficulty to make our observa- 
tions of them agree to within 3, 4, or 5 minutes of time ; but 
the belts on Saturn, which I have been lately observing, seem 
to have undergone no very material change, during the course 
of the two last months ; so that we may hope the period of 
the rotation of this planet, which will be assigned in this 
paper, may be looked upon as having a considerable degree 
of exactness. 
Before we can enter into particulars, it will be necessary to 
give the series of observations upon which my computations 
have been founded. It is not sufficient to extract only those 
parts of them which have served for calculating the period ; 
as the value of astronomical observations consists in having 
them entire ; every circumstance, as it occurred, is of conse- 
