RECENT CHANGES IN THE SURFACE OF JUPITER. 69 
changed in longitude. Finding the proof of its permanence so 
looked amongst 
show it in the same latitude and longitude as my own observations. 
The colour is there described as reddish and reddish Jeo. but 
no particular remarks are _— about it. Looking furt. 
found a drawing made by the keen-sighted ar on 27th 
November,1857, in which a acanilta form is depicted, but without 
— its latitude is the same, and the os also ; but too 
much weight must not be given to this, for a small difference in 
the period of Jupiter’s rotation (a rather uncertain quantity) would 
make all the na in such a long period between agreement 
and disagreemen 
groun 
form is no proof to the ential where clouds have so much 
uence upon visible outline, and the changes in form are r 
not great. At present both ends are blunt-pointed ; in 1876 the 
preceding end was round and the following pointed ; and from 
Earl Rosse’s drawings it appears that the preceding end was pointed 
and the following end rounded; and such changes are not important. 
I confess wegen that, before I collated my measures, the impres- 
The colour I have selected by esnia to represent the colour 
of the spot is by day-light of a htiok yellow, and when compared 
With a scale of colour which gives six shades between me and 
@ mar : 
It is worth note that the salle of a spot on 
were uminous this would not be the case. 
Measures oF THE Rep Spor. 
In June, 1876, it was 1380 long and 4”-60 in pee: on 
ber 3, 1880, it was 4”-°35 wide, the length was ot then 
measured ; on October 7, 1880, it was 15”-73 long and vo 28 in 
on October 28, 1880, it was measured again, 15”-00 
and 4” 26 in sre : 
€ writing about the persistent position of this spot, I may 
mention that, _ August 6, 1878, at _ 10m. p-m.; * saw a 
small white spot of striking brilliance, much brighter in fact than 
