54 REPORT—1849., 
which have since been obtained may perhaps not be uninteresting to the pre- 
sent meeting. 
About the beginning of February 1845, the instrument was so far finished as 
to be usable; and in the first instance it was directed to some of the brighter 
nebulz in Herschel’s Catalogue. Many of them were immediately resolved, 
and very frequently the aspect and form of well-known nebulz were com- 
pletely changed, fainter details not previously seen being brought out by the 
great light and magnifying power of the telescope. Before the end of April 
the wonderful spiral arrangement in 51 Messier was discovered. The specu- 
lum, though there was a slight defect of figure, was in fine working order, and 
defined with great sharpness when the air was steady. 
At the approach of the short nights, when the season for observing the ne- 
bulz was nearly over, the instrument was dismounted, as it was desirable to 
take the earliest opportunity of completing certain portions of the mechanism 
which had been put together in a temporary way in a rough state, and it was 
not till the close of the year that it was again in working order. 
During the year 1846 the examination of the nebule in Herschel’s Cata- 
logue was continued ; many sketches were made, and another spiral nebula 
was discovered, 99 Messier. The moon was observed occasionally, and the 
superiority of the instrument with six-feet aperture over that of three under 
equal magnifying powers, in bringing out minute details, was very remark- 
able; so great is the effect of light even when we have to deal with an object 
so bright as the moon with an aperture of three feet. 
As yet, however, but little time has been devoted to an examination of the 
moon: the moonlight nights have usually been taken advantage of for expe- 
riments on the polishing and figuring of the mirrors; and the information 
which has been obtained relates principally to matters of detail, from which 
it would be premature to attempt to deduce general conclusions suitable to 
the present notice. 
In the succeeding year, 1847, there was but little done; unprovided at 
that time with an assistant capable of making trustworthy use of the pencil 
and micrometer, and being almost wholly occupied with the duties incidental 
toa year of famine, it was impossible to do more than re-examine a few of the 
objects of the previous year. 
From the beginning however of the year 1848 till the present time, the 
instrument has been constantly employed whenever the season and weather 
permitted it, and the following are some of the results :—H. 604 was found 
in some degree to resemble the great spiral nebula 51 Messier, but it is a 
‘much fainter object, and appears to be made up of elliptic streaks disposed 
rather irregularly with a tendency to spirality, but without that distinct sym- 
metrical spiral arrangement which is so marked a feature of 51 Messier. If 
51 Messier were seen somewhat obliquely, and were considerably fainter, it — 
would probably very closely resemble it. 
H. 854, M.65, has an arrangement of very elliptic annuli, and is apparently 
a system of the same class seen very obliquely. 
M. 97, H. 838, is a very extraordinary object; with a dark hollow centre 
somewhat in the shape of a figure of eight, easily seen, and with a dise irre- 
gularly shaded, but showing in the shading a decided tendency to spirality 
when seen under favourable circumstances: two stars are placed in a re- — 
markable manner in the central opening. We may conceive it to be a spiral 
system greatly compressed ; the edges are filamentous: H 2205 has a faint — 
but large spiral appendage, to which the ray as figured by Herschel is insome _ 
measure a tangent. Several other nebule are recorded in our note-books as _ 
belonging to the class of spirals. The well-known planetary nebula in Aqua~ 

