The Great Comet of 1861. 307 
whilst the western one was not only irregular, as has been said, 
but its extremity was not as well defined, and the volume of that 
half was sensibly less. That boundary had notably flattened 
by 114 45m, 
The surface of the sector was much less mottled than during 
the night of the 2d, and was at no time so vivid as then. The 
dark oval spot could not be recognized. Beyond the sector there 
was a dark space, and concentric with and at the distance of 896” 
(measured by Mr. Ferguson) from the nucleus, a faint outer en- 
velope was traceable. This last was a narrow band of phat 
white hue, densest directly in front of the nucleus, at whic 
point it was 12” or 14” broad, and from thence diminished to- 
wards the extremities of the wings both in volume and luminos- 
ity until its form was that of a slendercrescent. _ 
he coma continued much as last night, and requires comment 
under two heads. The lower, or main portion, extending from 
the nucleus to half-way between * and 4 Draconis, was markedly 
the brighter, and the upper part of it slightly turned to the west- 
Ww. 
most extremity of the coma almost instantly, and again at others, 
€ whole volume appeared to be 
low branch by the wind. The most remarkable of these pulsa- 
ons occurred at 1050", during which the coma became ex- 
tremely faint between * and « Draconis, though it continued quite 
a above the latter star. Its greatest breadth did not ex- 
a 
_® Draconis was near the axis of the longer and narrower por- 
tion. This was nowhere more than 14° broad; was always faint- 
est between x and « Draconis, above which it was brighter, and 
could be followed in its gradually diminishing lustre to the east- 
Ward of « Ophiuchi where it was lost in the light of the milky 
Way, 
July 4—The gazing observations of this night 
7 50™ until 115 30m, P.M. 
continued from 
that of « Urses Majoris, When seen at a later hour it was more 
condensed than last night, and appear 
Pi 
At 10h the sector-shaped head prece- 
50™ the general form of ne oe teas distinctly marke i 
