2o5 
observed that the faint narrow belt upon which the upper end 
of the oblique belt rests, has increased in breadth and dark- 
ness in the portion immediately over the lower part of the 
latter belt, and has a faint spot upon it nearly central at the 
time the sketch was taken. 
Last night, April 25, a remarkable dark patch on the 
oblique belt was in the central position at 8h. 40m. : it was 
darker than the rest of the belt, and darker than any portion 
of the large southern belt. There was still the same contrast 
of colour, the oblique belt appearing to be bluish black when 
compared with the dull yellowish red of the large belt. 
Mr. Heelis, F.R. A.S., read a Paper “On the Observations 
of the Sun made by Hevelius in the years 1642 — 3.” 
The Author laid down the spots observed by Hevelius in 
the above years in a similar manner and upon the same scale 
as the charts of the solar spots made by Mr. Carrington, and 
communicated by him to the Monthly Notices of the Koyal 
Astronomical Society. 
From these he deduced the conclusion that at the time at 
which the observations were made the sun was fast approach- 
ing a period of minimum activity, which period he fixed 
as having in all probability occurred about the middle of 
December, 1644, and this period was shewn to be consistent 
with the statements of the observations of the spots mentioned 
in Lalande’s “ Astronomie” and Keill’s “ Introductio ad veram 
Astronomiam.” 
From the old observations, it appears that at the beginning 
of the eighteenth century there was a remarkable deficiency 
of maxima, inducing the suspicion that the period of the spots, 
or rather of the maxima of the spots, has a secular variation as 
well as the short cycle evidenced by the observations of Mr. 
Schwabe, although no range of observations has, as yet, been 
sufficiently prolonged to determine the period of such secular 
variation. 
