The Hawaiian gazette., 1874-11-18

IrOm the North pOia, q The hogison up through
the EenitA to The South poiel and vice versa Il
is a5jested with seeA esre, that the iussAnt o.
passage Of star over The meridian can Be deter
mined to tenth d second % tine. Evsry'
thing ahost II is solis. TIE mark Of reisrSeee So'
meridian is distant about three and a half miles
being located o. the Kalhi- MoanAloa TSdgS, side
By side with The Trsnsi, Is the AstrOaomieaI
ClOek. with eOnpeosssiHg pepdulem, mounted
50 as Dot to Be Jared BY any disturbing cause
Il movS With the stars. {. =, The sane star oesh'
TO cross the merriam st exactly the same hOa'
all the year road These t~O ioseparabls ins1rs
neots keep tine Of al observations
For the determination Of lAIitude and longitude
there IS il this observatory 81 AIranNvTa. This
term means simply most perfectly knisAed Tran
sit-tAeodolse, measuring all horizontal angles ard
nOrs especially IN this instance az rerael Gagiss
" unoaat q slsvation above The hoFiEou, or. q
speak more scientifically. all zeoilh distances
The instranent stands on pier Of concrete ma
sOory. Tue EeniIh pOint is determined BY PSir
Of euOstd delicate levels possibly to be obtained
The angles are measured % = l6-iDeh vertical
circle reading 20 seconds. and BY estiuasion to
fractions Of a seeood q are The reading Is done
BY foor compound microscope Tbs inslroineaI
will determine oar distance irOn the equator 10
within say Eve teet-s .t -.e
Nsxt. with vhieh1o sc the transit Of Veass,
&c, is the Equatorial Telescope, A SIX inch OBJ
jees gass-A tube say eight feet iOOg-eye-p pieces
furnishing maguifyins power Of from 50 70 I 900
dianeters. Ii is called an Equatorial because so
noGuted as TO move By cloek-wosk or otherwise
10 the plane Of the Equstot; that is to say, when
Oues pointed at star, it will follow tia, star in
its apparent motion through the heavens. More
over any star can be found by this instrument by
means Of the right ascension ard dselinAiion cir
eles. This is costly instrument, As may be in
ferred from the act lhatthe ls1s alone cost eight
hundred dollars.
FOgrIh and not least is the PiosaAeiograph-
photographic apparatus ADD Equatorial Tele-
scope combined. Il is beautiful highly finished
and most complicated instrument, one Of the only
Eve yet constructed Photographs Of the Sun are
taken in an in6nitesimal fraction Of time the
exact time by clock being also noted.
A uoIe should be made Of the O5TlI arrange
meat, or apparatus Tor daily practice 90 noting
the exact time Of internal contact Of the planet
veuus 90 the suns Iimb, By means OF mirror
the sun is made to sppear near the ground. 500
feet o. An artificial planet Venus Of the proper
size. is made TO pass over the edge OF this mir
rored sun-disk. 0bserTers with telescopes aud =
ehrononeter. practice daily at this so Important
q future duty also on favorable days using the
Photographic apparatus in the sane manner
Three uouths Of hard work night after night
eonseeatively viii De noue too much to accurately
determine all that will be needed with reference
TO the coming transit
Two branches Of the astronomical party have
been located elsewhsre-one at Kailua, Hawaii
ander Professors Forbes and BArnaels, and the
other at Waimes, Kauai. under Messrs. johnson
and Welings. Eseh party is supplied with
everything necessary to secure accurate observa-
tons of the transit 10 he event Of The sky being
clear from lis point Of observation. By making
three separate stations, the chances Of securing
the objects Of the expedition are increased. We
sincerely hope that nothing vii prevent the sue
cess desired.