The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1848-01-24


gage in astronomical pursuits You have hat
the subject, as far as this country is concerned
anxlousiy at heart tor years: wherefore consider
the present occasion as one for congratulation
Pardon, therefore, the DEPRESSION.
The astronom cal instruments OF the Obserga.
tory, with telescopes attached, are SIX. The
regular observers, eight.
LIST The West Transit Instrument, made by
Erlel & Son, of Munich. Observers, Mark II
echer. an Rael X 18th, Professors of Mathe.
mates, u. S. n
Pad, The Mural Circle, made by Tungh on s.
Sums, London, Observers, Thomas J. Page
and Charles Steedman, Lieutenants, and ]. IL
G Coffin, Professor OF Mathematics. u. s. N
81 The Meridian Circle, Ertel s.. Son OBJ
servers, William +. Muse, Lieutenant, anc
James MAJOR Professor of Mathematics, United
States Navy
An, The Prime Vertical Transit In strument
WAYNE, Lieutenant United States Navy, and
James Johnson Pittigrew, young matthew 4.
tlclaa from North Carolina.
5ih The Equatorial, Murz and Mailer, Mu.
nich. Occasional Observers, myself and 10.
seph ). Hubbard, Professor of Mathematics
United Safes Navy.
9th. The great 'Refractlon Circle Ere and
Son. Munich. Observers. none.
Lieutenant Page is in daily expectation of or
ders to sea, and Lieutenant Steedm N has been
in training TO take his place at the Mural. Hence
the names OF three officers for that instrument
Professor Hubbard has been recently detailed for
duty not connected Win tils observatory THen
he returns, he will observe regularly with the
Equatorial
A soon as practicable propose also to place
Professor Keith at the Refracton Circle
II is a rule among astronomers to consider an
additional assistant at an Observatory which has
as MANY as two observers already employed, to
be worth more IN an two better men at a new Oh.
servatory.
Considering that the expense Of buildings
piers and instruments has already been incurred
fOr g 4 IN
tormiy with the principles OF true economy TO
apply force enough to give the instruments tut
occupation whenever the weather will admit
than to have them only half manned, or feebiy
served.
Accordingly have constantly aimed to have
at least two observers for each instrument: sc
that when the light is clear there may always
be an eye for every telescope In the Observa-
tory.
But the unusual demand for officers ahoat on
the one hand and their anxiety for war service
on the other, have made 1t difficult, during the
last year, to keep at the Observatory its full com
plement of observers.
The West Transit instrument is mounted on
the Meridian in the West wing of the Observa-
tory. 1t has object glass of Sd inches aper-
ture, with focal length of feet inch. A clock
is an Indispensable companion OF thu instrument.
as time keeper OF some sort is of every astron-
omlcal telescope. The clock Is mercurlal
pendulum, by Parkinson and Frodsham.
The Transit instrument affords data for the de-
observation-disclosures rated, etc.
The Mural Circle, with the Merid IAN Circle, is
mounted IN the Z ist wing. 1t is 8 feet In dia-
meter and has a TELESCOPES with an object glass
of Al inches aperture, and feet focus. Mural
Circle is for the determination of Destinations.
By it latitude is also determined.
The Meridian Circle has microscope bearer
with microscopes, and circles of 80 inches
diameter, one for degrees and minutes, and the
other tor seconds, connected with telescope of
inches aperture, and feet ii inches focal
length Clock, mercurlal pendulum, Charles
Frodsham. This clock answers also for the
Mural.
This instrument untes the transit instrument
and the mural circle. 1t is for the determin alton
of both co ordlnates.
The prime vertical transit instrument is mount
ed on the prime vertical In the first apartment OF
the south wing 1t has no circle except a finder
The telescope has focal length of 81 feet and
s inches aperture. Clock, gridlron pendulum,
Charles FrOdsham.
This instrument is also for the determination
of right ascensons and declnations. But while
it is capable OF hi her degree of accuracy than
any one of the aforementioned instruments,
it is confined to more narrow field II
works more slowly 4; and cannot compete
with its compeers IN number or SUBJECTS OF
observation. They can observe all objects
that appear above the horizon and cross the
meridlan-it, those only which cross Its prime
verticnl-which In this instance embraces those
stars whose parallels OF declinatlon are included
servdtory.
The destinations determined with this instru-
ment are surprisingly accurate 1t is capable OF
atiording results possessed OF higher degree OF
accuracy perhaps than those obtained from any
otier instrument at present known to astronomy.
This is In part owing TO physical and mathemati-
C II advantages derived from It's position IN the
prime vertical, and partly to mechanical and IN
ment; 1t was Invented by the direction of the
Crntrl Observatory OF Russia, and this Is the
only other instrument OF the klnd except that.
Its position frees It's results from ami makes
them INDEPENDENT OF the effects and uncer-
ta,nties OF atmospherlcal retraction, and of
the numerous lmpertectlons and sources OF
error to wnlch lnstrum hts with grddua-
ted arcs and circles are liable. It's pecu-
Lar construction and extraordinary facii-
ties of reversal, neutraliZe other InsIrumen-
tai lmpertecions which are ,also fruitful sources
of error whenever their effects remain tor
The skill and patience OF the observer 10 detect
and expose. it Is particularly We'll adapted Tor
invesug ting the problem Of Stellar PdrrdilaX.
The equatorial has an object glass OF y inches
aperture and fourteen and halt feet local length.
IL is provided with clock work tor slderlai mo-
ton, and the observations are timed from side
rial chronometer rated by the clocks below. Ii
rests in tue dome, and surmounts massive block
of granite, which is supported by a conlcal pier
of brick work, rising from the foundation OF
the building and passing up IN Isolation oi the
floors and all other parts OF the Observatory.
plane of but one great circle, and capable OF OBJ
serving only as the object TO be observed crosses
such great circle, which, with the first three
named, is the meridian, and with the 4th and OH
the prime vertical
The object of the equatorial is TO observe oc-
cutations and eclipses, TO determine the places
OF comets and planets by dferential measure
ments. 1t is also used for measuring the angua ar
distance and position between double stars, tor
measuring the dlameters OF planets, etc. 1t may
be turned for observations ut any time upon object
in whatever part of the visible heavens Its greater
optical and space penetrating powers, invest its abors
in ysca astronomy with exceeding interest," and give
it other advantages which are not possessed by its
more humble companions bo w. though Tor diferental
position it is subsidiary to and dependent upon their de-
examinations
The Rsfraction Circle has two microscope bearers,
which carry six microscopes each two graduated
circles OF four feet each with divisions for every
two minutes of gold; and telescope Of in
ches aperture and eight and half feet focal length
This instrument is new In its combinations and con
strucon IL untes the exquisite accuracy OF the Prime
T-ap ins vii all tba al mt