1000000030

G R

P H T.

~ ~e

ediptic

perp~ndicularly,

and meet in

t\\lO

oppofite 'but

Ihe

~atitode

be fOolh, Ihof, llan whic11 lie uoda

!poiots io lhe poJar.cil:cles; which ¡poiots are each ninely tbe upper

par!

of Ihe meridian, belweeR Ihe north paiOl

<degrm -(rom Ihe edliplic, and are caJled ils poles. Thefe of. 'lhe henroo and the [ouch pole, 8re at their greatdl

:polar. point! divide thofe ·cireles iota

femicircles.; a1titude.

""hich.cut the ecliptic at

~'he ·b~giooiogl

of the

figos..

PaoB. IV.

'fhe

latilu~

the pJaoe, pnd daj

'They reCemble fa maoy meridiaos on the ter-rellrial globe,;

1he monlh, 6eing gi.v,"

;

Jo jind Ihe lime 'IJIh,n

a~,

;;nd as aJl places which.jie·under aOY'pll'n(lilar meridiano

IniJ'Wfljlar 'IJIil/ rifo,

.,.fu

IIPM Ihe 1I"ridian,

fel,–

femicircle on rhat glohe, have Itbe fame .Iangilude, fo all

Ha~in.&

re6lified che globe, , uro it abottt until the giveQ

tbofe poillls df ·the heaveo, qhrollgh which

~ny

of the

¡r-

,llar come! to tho eafier·n¡¡de of ¡he horizoD, and

th~

io·

:bove femicircles :lre drawo, have the fame ·Ioogitude.- dex will Ihew the time of the

Ilar'~

rifing; theo luro the

liad as.the

gre~telllatitudes. oo

the earta

a~e

at Iheoanh globe wefiward. and wheo !.he llar cornee lO Ihe brafea

;;!nd fouth pole! of Ihe eanh, fo the greatell latitudes io

nieridi~n,

tbe iodex willlhew

!he

.time of the nar!, ea.

~he

heaveoare at the oorrh and routh pales of Ihe eclíptic, ming to Ihe meridiao of your place; 'Iaflly, turo

00, UIl-

For the divifion of the llar! iot? coolfellations,

Oc.

fee til the llar comeHO the wellern lide of ¡he horizon, and

.AsTRONOM'i, p.

486.

the iodexwllllhew the time of¡he llar's fening . .

·PR.O'B.

.r.

1'0 jind Ihe ,,;ghl

afcenfl~n

I",d ¡{ecHnntion

lJ.

In oorrltero latitudes, mofe -Ihrs wbich are

.0/

Ih, fun, or anJ jixd jlar.-

Brin~

tbe fuo's place in Jefs difiaot rrom the oonh pole, than the quantit.Y'

oí

ití

the eclipticlo Ihe brafen meridian; then Ihal degree io-tlte e1evation aboye the oorth poiot

j)f.

the 'horrzon,

'ne,c~

-equiooélial whi,his ont by Ihe meridian, is Ihe fua!s'

right

fet; and·thofe whicb .¡re Jefs dillan! from the footh pole¡.

4cmji01f ;

and Ihat

degree.of

Ihe meridiaD which is over thaA the oumbor of degrees by which

id~ deprelfcd

beto"

'the (uo!s place, is his

declinoli.n .

Bring aay fixed fiar

~he

horizoD, never

rif~;

and

vrce vaf4

in foulhero l.'

the meridian, and its righ! afceofion wil! be cut by me liludes.

meridian io lhe equiooélial ; aod the degree ortbe meri.

PROB,

1'ojind'al quhaf 11me

IM)etl/'a.givuI

,diao that -/lands over it, is it! declination,

flar fJJJi/l ,b,

UPM

1·/,¿

meridian, al a· givt1/ hour

.<>{

~I,!

So Ihat tbe righl arcenfion and decliAQtion,

'08

lhe· cel~ .

n,ghf.-Briog

Ihe given·flar to tht .Uppef femioirclb

-/lial glcbe, are found in the fame maoner as longitude

tM.b~afs·ll!(.idian,·

aed (et{u·indek·to·tne gil'ell.llouf I

aod latitude O!I·the terreAria!.

Ineo turo the globe, unlil Ihe iodex poiots tO

·~t

PRon,

1'. jind Ihe laliule alld l.ngilu3e. •f atry

'oooo, :md ihe -upperfemiclrcJé ohhe lIleridiiMl wUI tben

jlar.-If

the giveo 'flar be ·on

~he

north fide

01"

Ihe eclip- cut the fuo's place, a¡lfwering le the <laf cf the yen

tre,

placeIhe 90th degree -ofthe quadrant of altitude

fougilt; whioh day may be eafily.fOllad agaiotl the liks

the norrh'pole ef Iheecliptic, whene!he twelYe femicircleo pldce of tbe fuo ·among the figos

Ihe wooden hOlizon.

'I11eet, which divide 1heediptic;inlo ¡'he i2·iigns: but

PItOB. VI,

he loNtud" '.j oflM

11W11 Ó;

and

.%il/INI~

1he llar be

the fouth ,!ide of the ecliptic¡ place the90th

4f any

~1/"""n

jlar, heillg giVM';

jind Ihe hour'of Ihe

degree of the q\ladraol on the ·fouth poIe of the ecliptic,;

,.ighl,-Há~ing

reéli6ed tbe globe

ro.

dIe Jadtorle¡· ze–

Jmpiog the 90th degree of the quadrant oo.tlle

p~oper

nith., a04 [un's place, lay Ihe .qoadrant of a¡tilUde tO me

pole, turo the '!'ladrant aboüt, uotí! its graduated edge . ¡¡iven degtee of azimutb iR the horizon ': then lurd lb(

>cuts the llaT.: meo, the oumber of degFees in the ,\ua· . ,globe en in axis, until '!'be (br comes

too

the graduated

<lraot, betweeo the ecliptic aod the fiar, is ils htitude; edge of the 'quadratlt; ;¡nd 'll'n.:o

dUel, me -inda wilJ

aod Ihe degree of the ecliptic, cut by the quadraot, is ,poiot OUI tbe hour of me ilight.

the llar's loogitllde, mkooed according

«o

the fign iD

P.RilB,

VI1.

1'he latitude of

,h~

place, Ihe daj

which the quadrant Iheo is.

Ihe

'M~lh,

tllld

Qf¡;I.¡/~

oflIoj.b()'Iinjl,e,

:~.ing.!iVlo'¡

PRo

llL

Toreprefenl tbe face of Ih, jlarry jir· /opad

I~e

h'4JJr

Ihe

rrighl.-Reélify the globe as i,othe

"al11.e1fI,' al feen from' /In) groll1 p-Iace

Ihe egrlh, al

for.mer

probt~m,

guefs at the ·hour of the oigbt, aod tUtll

anj hour

Jhe.

ni8hl.~Reélify

the

celefii~l

globe for

th~

globe unüJ die index points at the fuppofed hour ;

the giveo latitude, the zeoitn, and fuo's place, in every then lay the gra4uated edge of the"luadrao! of ahitude

refpeét, as 13ughl by the XVlth problem, for the ter- over Ihe koolYll llar, aod if the degree of the fiar's height

refirial; and turo it about, umillhe index poinu to the io the '1uadranl upoo the ¡}Iobe, anfwers Cl<aéHy to the

giveo hour: tnen, the upper hemifphere of the globe

deg~ee

of lhe fiar's obferved altitude in the heaveo, 'you

will repref¿"t ílie : ..iGble half of the heaveo. for that

~ave

gudfed exaaly : bu\ ir the (lar on Ihe

~I.obc

is high.

time; alllhe flan" upon tho globe beiog theo io (tlch er

JOlI'er.than

,'1

was obferved to be io the' heaven,

¡¡tuations, ·as exaény co<fefpond

10 tllofe

iR the.

~ea.

Itlfa-the

.glebe bacl\.wards-o<- for.wards, k«ping the edge

And if theg10be be placed<luly north artdfouth ,by mean, of the quadrant upon the llar, until it! cemre comes to

of a fmal! fea.cOUlpafs, every (lar in Ihe

glo~e

will poiot '.the

-oble~va:h¡jritude

in the quadraoT'; and tbeo. the in.

toward the Iike Itar in.the

hea~en;

which means, Ihe

ileK

",ü1Ih~w

tbe true time of the night.

conlleUationl, and rtmarkable lIars '1lay'be eaGly knowo.

PI·ClB.

VIU..:

tajj II/Ilhodfor

fintling.tI"

h()fjr of

,A1l

tho.fe

fIars which are in theeafiern fide oflhehorizoo,

.'Ihe nighl bj allj I'IJIOln...

'7l

jlarl, 'Wilhoul

~no'U,ing

ti.

are Ihe.n rifiog in the eallero fide of the11eaveo; all io the

Iher Ih,ir al(itude .cr

4zi/IJ~lh;

and Ih,n,

findin!

wellero, are fettiog in the wefiero fide; .nd aH thoFe

bolh Ihrir d/rilud, and ¡fZi1llUlh, D/ld IAl/ehj Ih,

Ir"~

under the upper pan of the braren meridian, betweeo the

IMt'idian .-

Tie ooe eod of a Ihread

acommqnmuOtet.

fouth point

óf

tlle borizon and the north pole, are at Iheir bullet ; aod, having reélified the globe as above, hold

greate!l ultitude, if the latilude of the place be north: the oth'er eon of the thread in your haod, a'né carry k

VOl., Ti. No.

SS'

J1o.\\'1y