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was even suspected in 1810, which its re-appearance on the present occasion 
strongly confirms. It was discovered in America on January 8 (indepen- 
dently), and the astronomers of that country are also of opinion that the 
three comets are identical. 
Distance of the Moon. — Closely following on the improved knowledge 
of the distance of the sun comes that of the moon. The mean distance of 
our satellite was determined by Professor Adams as 238,793 miles, and this 
result has been generally adopted. From a laborious discussion of the 
lunar observations made contemporaneously at the Cape of Good Hope 
and various European observatories, Mr. Hugh Breen has determined that 
the above distance must be diminished by 26 miles. Mr. Breen’s result 
has been adopted in the “ Nautical Almanac ” of 1867, and will doubtless 
be generally made use of by astronomers. It has thus been found that 
we are nearer both to the sun and moon than was formerly suspected ; 
but the correction to the distance of the latter body is small in com- 
parison with the four millions of miles by which we are found to be 
nearer to the former. 
Variable Nebula in Taurus.— On a beautiful observing night on December 
12, Mr. Hind looked for this curious object with the same telescope which 
he used on the night of its discovery (October 11, 1852). Not the least 
trace of it could be seen ; but the star which almost touched it was 
equally perceptible as in 1852. Strange to say, this latter object is also 
variable. On the same night his assistant, Mr. Talmage, who could dis- 
tinguish eleven stars in the Pleiades, was equally unsuccessful in detecting 
any nebulosity. 
Nebula of Orion. — Mr. Stone examined this nebula with the Greenwich 
refractor on January 11, and is of opinion that the drawing by Sir J. 
Herschel is more accurate than that of Professor Bond, particularly about 
the so-called jaws. The drawing of Professor Bond gives a squareness of 
outline, and an almost total absence of light within the jaws, which is not 
seen by the Greenwich observers. 
Supposed Lunar Atmosphere. — Professor Challis controverts the Astro- 
nomer Royal’s argument in opposition to his theory explaining the pre- 
sence of a bright band bordering the edge of the moon, as seen during a 
solar eclipse. The Astronomer- Royal, he states, takes the case of a mean 
atmosphere, whereas his explanation supposes the existence of one whose • 
density decreases with its height. 
Light of the Moon at Total Eclipse of June 1 . — The Astronomer- Royal 
compared the light of several stars with that of the moon on the above 
occasion. Being short-sighted, the stars appear to him as large luminous 
discs, similar to the moon. He thus found that the moon’s light exceeded 
that of Antares and Spica, somewhat exceeded that of Alpha Ophiuchi, 
and was a very little less than that of Alpha Aquilse. 
Star Maps. — The magnificent catalogue and star maps of Professor 
Argelander are now completed — the number of stars registered amounting 
to 324,198 altogether, which are visible in the northern hemisphere with a 
telescope of 4% foot focus. The preparation of this great work has taken 
upwards of seven years, in which there were 625 clear nights, and the 
number of observations amounted to more than a million. The month of 
