62 
LOED OXMANTOWN ON THE GEEAT NEBULA IN OEION. 
lous. It is, however, of little intensity, and offers nothing remarkable enough in respect 
of form to make it worth while to enlarge the dimensions of the engraving sufficiently 
to include the whole.” 
He also says (page 29), “ Northwards between this nebula and C Orionis; .... no 
nebulous connexion has been traced.” 
With regard to the extent to which the nebulosity can be traced with the 6-feet tele- 
scope I do not find any record by Mr. Bindon Stoney. He appears to have confined 
his attention entirely to the central portions, except in the following instance, where he 
remarks — 
“Nov. 25 th, 1851. There is a long dark channel following theHuygenian region by 
about the diameter of the latter, in which no nebulosity exists, and twice on good nights 
with a freshly polished speculum it gave me the idea of immense depth, like a gulf 
without any bottom ; ordinarily the light from the surrounding parts spreads a faint 
light over it. Comparatively few stars follow this part of the nebula for about 80'.” 
With reference to the extent of the nebulosity, Mr. Hunter says, “ It has been repeat- 
edly traced up to the star i Orionis on the south, and on several occasions to C Orionis 
on the north, while in the preceding direction the sky assumes a peculiar milkiness, at 
least one degree before the nebula comes into the field. In the following direction it 
does not seem to extend much (about 10') beyond the limits in the sketch.” 
“ Between the stars 135 and / Orionis the nebulosity narrows to a band of about 5' in 
breadth, and then again expands as it approaches / ; there has been no attempt to trace 
it further in this direction.” 
“ Again, the nebulosity curves round from the star 6 in a north preceding direction 
until it joins a narrow band of faint nebulosity, passing in the preceding and following 
direction through the little group of stars of which C Orionis is the brightest.” 
On many occasions I have examined the neighbourhood of this nebula with the view 
of determining, as far as possible, the extent of the nebulosity. On the following side I 
was able to trace it 35' following the trapezium ; this nebulosity was, however, exces- 
sively faint, and of almost uniform intensity ; in fact the only proof of its existence was 
the prolongation of the dark lane extending through it from the star 142 t , which made 
the surrounding region look slightly luminous by contrast. On the north side the 
nebulosity appears to be nearly cut off short by the same dark lane which extends by 
the stars 114, 56, 25, 1 X1V . At the last star this ceases, and a faint broad streak of 
nebulosity appears to curve round in the direction of C Orionis, nearly in the position 
described by Mr. Hunter. On the north side of this lane the nebulosity seems to begin 
again, and gradually increases in intensity to the streak at C Orionis, the brightest part 
being perhaps rather fainter than the nebulosity round /. 
On the preceding side the nebulosity appears to extend to a great distance, and seems 
to be of the same character as that about the stars 0 IV , 0 vm , l n ; the streaks, however, 
gradually diminish in intensity, and though, when followed by the eye in the preceding 
direction, they may be traced for some distance (5', or in some cases perhaps 10') beyond 
