The Use of the Globes.

tVi

^ tflC Ter re/trial i but shall first premisee following Definitions relating thereto.

I. The

5 C the Hour of his being clue East or West,

£ ~ C G the Latitude of the Place.tst e ' Pappose the Sun in the liorizon at M once more $p the Right-angled Triangle M C R we haveS M the Amplitude from East to West.i~R the Declination North.

■p R the As.ensional Difference.

^ C M the Co-Latitude of the Place,fc R M C the Angle of Position.

' the oblique Triangle A Z N we havepp N the Co-Latitude of the Place Z.

N the Co-Declination.

. ^ the Complement of the Altitude AT.

"rN Z the Hour from Noon equal to Æ X.

N the Azimuth from the North,

Qt her to iamc mav he done for any Star at A, or any§ ^ace.

"lY;’ lastly, let Y be any Star, then in the obliquelan y §R fN Ewe have *y R the Co-Latitude of the Star.

-X N the Co-Declination of the Star.j. E = Æ as == the Obliquity of the Ecliptic,j, R Y the Star’s Longitude in the Ecliptic,q Y the Hoar from Midnight. :>

°r the Canons and Method of Calculation I shalls- he Reader to the second Volume of my Young* U 0> t leter ’ S Guide , wdiat I have done being as much

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the

last

••‘eccr s ijuiae , wna: j. nave uuuc ucmg uwuiNature of the Subject at present requires : Andw h° have no Globes may solve most of these (and4 t a v 0( Rer) Problems by my ’Synopsis Scientia Cæle/lis,

1 'es s _ er y small Expence, and with the greatest Exact-

^ be Reason of the Pbanomenon we call thejhay ® s T-Moon is extremely easy by the Globe, and1 the rr be . re prefented in a Diagram thus. Let H O“e the ^ tizon, ÆQ_the Equinoctial; then will T r PlateEcliptic, when the Beginning of Aries is in the LXVI

0 0 ttt n . r ?: _

T 4

Western Fig. 2 .