H„f eCod

Astronom .y*

Width arid Distance from Saturn's

CXII. The Se-ef a Place from my

Let the Moment of Time in which the

tli Mll te p '* me ivromenx oi x ime m wm<.n

I c &iv-e n vf rs ^he Shadow of "Jupiter be calculated fortS ^Meridian from Tables of its Motion; then

%

jMh e ^Meridian from Tables of its Motion ; thensutlers- ornent of Timfe be well' observed when this

St< a ' ■ ■ -

bar

Se 0 f' / ,d PP e ns at the proposed Place ; the Dif-P* tile s fle ^ e two Moments turned into Motion will •. 'Sig j „ ^gitude of the Place for that Meridian, al-^tes Cgrees sor ever y Hour, I Degree for everyer y fyr;„ Time, or it Minutes of a Degree for

L 9 :t'ft° f Time. .

titter f r third Problem is, to find the Distance of-Thddlg A* ^ un - This is done as follows: Letf 6 ]j he 0 i .. °ment of the Occultation of a Satellite as■ °Wir,„ ^tved, and again the middle Moment of thef 5 this will give the Time in which the

125

of ; are equal, and computed at upwardsa^ 0 ’ 000 Miles. The Periodical Timesijj g ^stances of the Saturnian Moonskity ^Eatneters of the Ring are as sol-.

, Firjl, or inmost, t evolves aboutTn in 1 Day, 21 Hours, 18 Minutes,.

at

y the y I she First of which is, to determine the Rath'1 hay e e °fity 0 f Ligh ti -Xhe Manner how this is done; s e ^hereThewn : See Annot.

'defied Ermine the Longitude jl n g kJ Pridian ; which is easily done bv the follow-

Si ss- - ‘

F1-.

8 .

Hol.V described. Then say, As the i fo ^ ^^h 0 i solution is to the Time no ’ an d Mi-

S Si?' ® therefore

hie °htamcd in the Arch 1 G , * , p I S,

of the Angle FIG, «being-bioi* ls the Parallatic Angle at Juptei , - jg is

Distance of Jupiter from S',v^y[V.^ n > by what has been ihewn in Annot. t XX