The Great Comet of 1861. 253 
that this was the tail of the same comet. The daily newspapers 
report that the head of the comet was seen on Saturday evening 
at Columbus, in Ohio, but it is not known that any one made 
any accurate determination of its place. 
On Monday night at New Haven the sky was overcast; but 
on Tuesday evening July 2d, the sky was mostly clear, and the 
Dec. 63° 5’ N. Seen through a telescope of five inches aper- 
ture, with a power of 55, the head was fully thirty minutes in 
diameter. Near’ the center of the nebulosity appeared a very 
brilliant nucleus, from which emanated a luminous sector, whose 
Opening was about 90°, one side being nearly vertical and the 
other or right side was nearly horizontal, This brush of light 
extended two minutes from the nucleus. The tail of the comet 
could be traced to a distance of 90° from the head. 
On Wednesday evening the sky was again clear, and the 
Comet was observed to great advantage, but its brilliancy had 
pepehly. declined since Sunday evening. At 9% 5™ P.M., its 
ead was in R. A. 98 52m and -Dec. 66°10’ N. Seen through 
the telescope, the coma had about the same extent as on the 
pearding evening, but the luminous sector already mentioned, 
ad changed very noticeably. The sides of the sector were 
curved, the concavity being outwards, and the opening of the 
Sector amounted to 136° when measured to the extremities of 
its arc, but the initial directions of the two sides formed an 
angle at the nucleus of about 90°. From the nucleus to the 
edge of the sector was 1’ 34. Beyond this, there was a dark 
arch or band concentric with the nucleus, and beyond the dark 
band a luminous arch or envelope faint and misty, the middle 
line of which was 2’ 56” from the nucleus. Beyond this there 
Were faint indications of a second envelope, with an intervening 
tk arch, the whole forming a series of nearl concentric light 
and dark arches, similar to those observed in Donati’s comet in 
1858, and in Halley’s comet in 1835. The tail of the comet on 
Wednesday evening could be traced through an are of 95°, and 
the deviation of its axis from the position of direct opposition 
the sun was about 12°, and ane me east, oy axis produce 
cutting the ecliptic about 8° bebind the sun’s place. 
hie tail of the comet was carefully observed on several clear 
evenings, but the observations were more detailed and complete 
on the evening of July 8d. The northern edge grazed the star 
Lambda Draconis, passed about 15’ to the south of — Dra- 
Conis, and continued on through Iota Draconis, and far beyond 
it, in an are of a great circle. The southern edge passed just to 
; i H. 30, Ursae Majoris, 
and continued on through the stars 3 and 8 Draconis. (Accord- 
