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THE PLANET JUPITER, 1869-1870. 
By the Rev. T. W. WEBB, M.A., F.R.A.S. 
T HE singular appearances presented during the late season 
by the planet Jupiter have naturally received, as indeed 
they have deserved, much attention from astronomers ; and in 
many instances no doubt from those possessed of optical appli- 
ances, as well as eyes, superior to my own. This consideration, 
however, has not induced me to withhold a series of observations 
which I undertook as far back as the middle of October ; for 
every original contribution to our general store of astronomical 
knowledge may possess a certain, though it may be a very 
subordinate value. As regards astronomical phenomena in 
general, a comparison of descriptions and representations by 
various eyes and hands, and in the use of different telescopes, 
points very distinctly to the conclusion, that where so much of 
personal and instrumental equation exists, a collection of in- 
dependent details from any fairly reliable quarters may not only 
be permitted but recommended: in such an accumulation* 
though error must necessarily be involved, there will be a con- 
tinual increase of the elements of truth. The readers of the 
present paper will therefore be content to take my statements 
as they find them. I have attempted to describe simply what 
I have seen ; not doubting that others may have seen more* 
and understood it better. 
An important distinction has been repeatedly pointed out, 
between the group of interior and exterior planets, as referred 
to the wide interval now known to be occupied by a multitude 
of minuter bodies. Either group, as far as observation extends, 
or fair analogy will carry us, has a character peculiarly its own ; 
the outer being distinguished from the inner by inferior com- 
parative density, but superior magnitude, velocity of rotation, 
and attendance of satellites. These remarkable differences, 
though increasing the interest of such researches as may be 
permitted to us by the Great Ruler of the universe, add mate- 
rially to their difficulty ; and we find it impossible to carry on 
to remoter planets the analogies which have apparently served 
