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yet the Greenwich Tables have a world-wide
reputation, and some of them are used as the
groundwork for calculations in all Observatories
at home and abroad. The astronomer
does not want marble halls or grand saloons
for his work. Galileo used a bell-tower at
Venice, and Kepler stood on the bridge at
Prague to watch the stars. The men, not the
buildings, do the work. No disappointment
need be felt, then, to find the modern
Observatory a range of unadorned buildings
running east and west, with slits in the roof,
and in some of the walls. Within these simple
buildings are the instruments now used,
displaying almost the perfection of mechanical
skill in their construction and finishbeautifully
adapted to the object they have to fulfil,
and in perfect order. They are fixed on solid
piers of masonry, deeply imbedded in the
earth, to secure freedom from vibrationa
quality better obtained when the foundations
are on sand or gravel than when on rock.

To describe the instruments by their
technical names, and to go into any particulars
of the instruments they have superseded, would
take space, only to do the work of a scientific
treatise. Enough, therefore, to say that there
are the telescopes best adapted to the chief
duty of the place, which is, watching the moon
whenever she is visible; watching the clock-
stars, by which the true time is calculated
more exactly than it could be from observations
of the sun alone; and watching other
planetary bodies as they pass the meridian.
Eclipses, occupations, and other phenomena,
of course, have their share of attention, and
add to the burden of the observer's duties.

The staff of the Observatory includes a chief
astronomer, Mr. Airy, with a salary of £800 a
year; and six assistants who are paid, £470,
£290, £240, £150, £130, and £130, respectively.
This does not include the officers of the
Meteorological branch of the establishment, to be
spoken of hereafter; and which consists of Mr.
Glaisher, with £240 a year, one assistant at
£120, and two additional computers. At times,
when these scientific labourers have collected
more observations than they are able to work
out; additional help is summoned, in shape
of the body of scientific clerks before spoken
of; who, seated at desks, cast up the accounts
the planetary bodies, including such regular
old friends as the moon and fixed stars, but
not forgetting those wandering celestial existences
that rush, from time to time, over the
meridian, and may be fairly called the chance
customers of the astronomer.

Though the interior of the Observatory
seems so still, the life of those employed
there has its excitements. Looking through
telescopes forms a small part only of
their duty-- and that duty cannot be done
when the weather is unfavourable. On
cloudy days the observer is idle; in bright
weather he is busy; and a long continuance
of clear days and nights gives him more
employment than he can well complete.
Summer, therefore, is his time of labour;
winter his time of rest. It appears that in
our climate the nights, on the whole, are
clearer than the days, and evenings less
cloudy than mornings. Every assistant takes
his turn as an observer, and a chain of duty
is kept up night and day; at other periods,
the busiest portion of the twenty-four hours
at the Observatory, is between nine in the
morning and two in the afternoon. During
this time they work in silence, the task
being to complete the records of the observations
made, by filling in the requisite columns
of figures upon printed forms, and then adding
and subtracting them as the case requires.
Whilst thus engaged, the assistant who has
charge of an instrument looks, from time to
time, at his star-regulated clock, and when
it warns him that his expected planet is nearly
due, he leaves his companions, and quietly
repairs to the room where the telescope is
ready. The adjustment of this has previously
been arranged with the greatest nicety. The
shutter is moved from the slit in the roof, the
astronomer sits upon an easy chair with a
moveable back. If the object he seeks is high
in the heavens, this chair-back is lowered till
its occupant almost lies down; if the star is
lower, the chair-back is raised in proportion.
He has his note-book and metallic pencil in
hand. Across the eye-piece of the telescope
are stretched seven lines of spider-web, dividing
the field of view. If his seat requires change,
the least motion arranges it to his satisfaction,
for it rests upon a railway of its own. Beside
him is one of the star-clocks, and as the
moment approaches for the appearance of the
planet, the excitement of the moment
increases. 'The tremble of impatience for the
entrance of the star on the field of view,' says an
Edinburgh Reviewer, ' is like that of a sportsman
whose dog has just made a full point, and
who awaits the rising of the game. When a
star appears, the observer, in technical
language, takes a second from the clock face; that
is, he reads the second with his eye, and counts
on by the ear the succeeding beats of the clock,
naming the seconds mentally. As the star
passes each wire of the transit, he marks down
in his jotting-book with a metallic pencil the
second, and the second only, of his observation,
with such a fraction of a second as
corresponds, in his judgment, to the interval of time
between the passage of the star, and the beat
of the clock which preceded such passage.'

An experienced observer will never commit
an error in this mental calculation,
exceeding the tenth of a second, or six
hundredth of a minute. When the star has been
thus watched over the seven cobweb lines (or
wires), the observer jots down the hour and
minute, in addition to the second, and the task
is done. Stars, not very near the sun, may be
seen in broad daylight, but, at night, it is
requisite to direct a ray of light from a lamp,
so far to enlighten the field of the telescope,
as to permit the spider lines to be seen