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equatorial belt from two other points in the large dark belt. 
The spot at the lower end of the oblique belt was central at 
9h. 41 ^m., Greenwich mean time. 
March 21. The oblique belt had increased considerably, 
and the spot at its lower end was much larger and appeared 
to consist of two spots in contact. 
April 5. The following part of the oblique belt had 
undergone a considerable change, and had now three spots 
or rather large patches upon it much darker than the rest 
of the belt. 
April 9. The oblique belt now extended over more than 
a semi-circumference of the planet, as it was seen at 8h., 
Greenwich mean time, extending completely across the disc. 
Its extremities were, however, still on the same parallels of 
latitude as when first observed by Mr. Long. 
April 20. The preceding end of the oblique belt was in 
its central position at 8h. 23m., Greenwich mean time. It 
was much darker than the rest of the belt, and was estimated 
to be two or three times darker than the darkest part of the 
large belt. Its colour was also very remarkable, being bluish 
black when contrasted with the dull yellowish red colour of 
the large dark belt. 
From the observation made this night, it appears that since 
Mr. Long first observed the oblique streak on February 29, 
it has gradually extended itself in a preceding direction, or in 
the direction of the planet’s rotation, with a mean velocity of 
3,640 miles per day, or 151 miles per hour; its two extremi- 
ties nevertheless remaining constantly on the same parallels 
of latitude. 
Fig. 4, taken April 22, at 8h. 25m., Greenwich mean time, 
shows the two ends of the oblique belt on opposite parts of 
the disc, the preceding end coming on and the following end 
going off. 
April 24, at9h. 20m. The following end of the oblique belt 
was in the position shown in Fig. 5, in which it will be 
