Weekly national intelligencer. [volume] (Washington [D.C.]) 1841-1869, 1848-06-10


uheuiy about the exact instant of internal contact owing
10 certain phenomena Of light which prevented the planet az
tna instant nom appearing perfectly circular The edge nearest
tue hmo OF tue sun appearing into band or IN
spread into drops that the time of the first internal
was delayed, and that Of the last accelerated However
ken altogether no other method yet proposed seems 10
proach this In accuracy and very full discussion Of The al
seryaions oil 1863 by number OF astronomers Encke
the rest have fixed the parallax at eight seconds and %
eghthundredths very good article upon lis aroonnt IL
DE feer will be found in the fifth volume Of the Transac
TONS OF the Astronomical Society and observed by him
and confirmed by Encke that the amount lust mentioned ~
eight seconds and Observation-Disclosures the mean paraIay
without likelihood OF amounting three hundedths
OF second The whole may exceed this but !, i
doubtful if it exceed fse hundredhs of second of snos
Now, is proposed by of observations made as be-
fore remarked In this city, and upon the of South
Americas TO eliminate this if it exists Is this Of prac
Teal Importance And, II IT he, it be effected BY the
method proposed to US by the Committee on Naval Affairs
Mr. Chairman, must be confessed that, considered purely
as scenuhc question: this is OF great importance and
well worthy the attention Of this committee Il is matter az
congratulations sir, that the gentleman from Tennessee r
STASroN has reported this amendment from the Committee
on NaVa Affairs From this country much due the cause
OF science and but little has been paid No other has derived
greater or more lasting advantages from the scientific nves
cations and astronomical observations of distinguished Epro
peans made under the direction of The several Governments
OF that continent and until lately, has done less TO re-
turn the obligation IL by OF their labors that COM
merce has been made to expand and that navigation has been
rendered easy and there doubt but that those y
labors have conduced TO make what we areoe If the
very greatest naval Powers OF the world Common Justice
therefore, requires OF repayment that too shou
contribute our just proportion the common stock Of scientific
research and scientific investigation But sir we are accus
toned TO consider every question practically to desire that
every enterprise undertaken by may be speedily successful
and make quick OF profit We are ant 70 reou;e
that the immediate result of every undertaking should at once
be clearly and palpably visible then becomes ques
ton what immediate gain shall derive from this pronosd
expenditure Shall thereby is suggested in the report
OF the committee, facilitate the solution of the problem Of the
longitude
~
Mr. Chairman, if this were to be the result one would
doubt for instant, is be hoped indeed for other
reasons that will doubt of the importance of this ex
petition but candor renders necessary say that we are
not key by future researches into the amount of the
sun parailax, 10 enable navgaors determine their posi-
ton at sea with greater accuracy than that which has al
ready been attained. that of the periodical in
equaltes OF the moons motion in longitude is dependant
Tor It's amount upon that OF the suns paraax that therefore
the perfection OF the lunar tables in measure defendant
upon the asceanment paraax and as the method of
lunar distances for determining the longitude at sea is largely
IN use, may follow that the question at present under dis
cuson connects itself with that Of the longitude which lat
ter one oil great Importance aud well worthy the serious
attention OF this committee. But, Mr.. Chairman we NAV
perhaps safely conclude, if the probable error of paraa. he
three or even live hundredhs Of second that correction to
hs amount VIII be mpercepbe in IFS effect upon the lunar
tables Again, 1t may be- said that in the method of lunar
distances for the determination Of the longitude the paralax
enters directly as an element into the computation that when
the angular distance apart of the and sun is taken this
correction must be applied the observed altitude of the sun
or that Venus be observed with the moon the allowance
OF her paralax in altitude corrected by the observations
proposed 10 De made, matter OF importance it
Is pretty evident that these corrections extremely minute
and such taken into account by practical nay
gators difference from the truth a minute or two
IN the attitudes not of considerable Importance while such
an error IN the distance would be fatal Indeed the whole
amount of the paraax in altitude may be merged in other
corrections for example, in that for the Dip which depends
upon the altitude OF the observers eye above the level the
sea- The common allowance made when the lower limb Of
the sun Is observed Is twelve minutes addve
ton OF its altitude of paraax dip and semi
diameter such small quantities those now under discussion
being neglected, as in fact the instruments sea- both
Tor the purpose OF measuring the attitudes the distance
are incapable of approaching Them. Enough Mr. Chairman
has been said concerning the beang of this problem upon
that the longitude which, il again repeated il believed
will not be materially affected by small corrections Of paaax
next question is, will the suns paalax probably be
altered by the proposed observations for upon the amount
OF this paaax dependant knowledge Of the dimensions
OF me planetary system, the earhs seidameter being used
as base Tor that purpose and the diameter Of the earth orbit
afterwards IN order to determine the annual paraax of those
liked stars whose paralax is appecabe said to be in
few cases. becomes important determine the suns pa
ralax with The last degree accuracy and here Mr. re-
marked, there appeared to be some doubt MANY
OF the observations viii OF necessity to be made al yery
low attitudes OF the planet when there will be difficulties
arising from refracon which may themselves be different at
the northern and southern observatore besides when extra
mendonal observations reorted the small stars will NOT
be visible admit Of accuracy Of comparison at any con-
siderable attitudes and this would SEEM BY referring 10 the
report OF the committee to be the opinion of those distinguish
ed astronomers Encke and Gauss Other gentlemen how
ever, had formed favorable opinion of this method and
Mr. E. observed that he would pretend for single instant
place his humble judgment conflict with that Of persons
distinguished IN the science of astronomy. With regard 10
any great alteration in the Of parax might be ne
cesary here to remark upon its amount asceraned by
method entirely independent of any OF those previously COM
mented upon IN order to whether likely to arrive
at such result Lapace, in the seventh book Of the Me-
canque Celeste had determined the paraax by means Of the
paallactic inequality in the moons longude and had re-
marked that this method of determining
the suns paralax BY his computations he had fixed its
amount at eight seconds and fxysx the COM
miee will perceive, within hundedbs Of second Of the
amount determined by the of 1852 This NAV then
be taken cooboave of the received amount and as for
her to believe that but little alteration will be made in
IT, But, although but little if any alteration Of the amount
OF parallax received may be expected from this
expedition, much good may undoubtedly, Mr.. Chairman be
predicted OF iii do alter that amount il may at least
suffice to coroborate and to confirm il this result only
be clearly and evidently effected benefit will be conferred
upon science far beyond the amount which is proposed to
appropriate and s that is the effect which may be expect
ed Of this expedition But further indirect advantages both
IN scientific and practical sense, will in all probability flow
from It, The positions of many Of the Of the southern
hemisphere will be asceraned with greater accuracy and the
observations upon the planet itself will be without their
advantages TO say nothing Of the great quantity OF useful
formation, unprotected in the beginning, which always flows
from an expedition Of this character Sir this may find lis
illustration IN the vast labor Of mathematician the improve
ment Of analysis and in the solution Of problems apparently
the most trivial in themselves and far human vision
could discern the urhest removed from any practical npp