527

g

can now ^ ^ lese ^ atte r results and the Solar Tables, weThus, Su l r ° m . l ^ e s *^ erea l time, find the mean solar time.® re enwich^° Se ^ Were re 1 u ^ re ^ to find the mean solar time atfin»e hv tv, * ^ A "g ust 1821, when the corrected sidereal3 ne c '°ck was 20 h 42 m I9*.4.

By the S °lar Tables,

Q f

Un s e P°ch for 1821. 9’ 10° 48' 19‘.2

mea » motion to August 20, .... 7 1? 41 4.2

= 9 h 53 m 57*.540 0 0.47

mean longitude of Sun on Aug. 20, 16 28 29Reject lo® i

> and convert the remainder into time, and

now e 4 ' 28 ° 29 ' 23 "* 4 .*

e 9 u ation of equinoxes (see p. 376,> .

Sun’s r

at r 6311 * 0n ^' tu< ^ e on the meridian |but tr reenwich on August 20, 1821

true sidereal time.

^iff. of »

°f * li etWeei1 ^ un a,, d the point 1a ubtr 6 ^ leavens on ^ ie meridian J^ see P* 526,) the acceleratic

ar time when the sidereal ltime '

Was 20 h 42 m 19".4

)

.9

53

58.01

42

19.4

48

21 .39

.... 0

1

46.216

46

35.17

by ^ one Use of this operation (the conversion of time shewns °lar t' tr !" sit a star, or by the sidereal clock, into meanof c j lr e ' ls the correction, or the means of ascertaining the rate,n oiu e tg r n ° nieters * ^ or 'ttatance, in the above case, if the chro-> at the instant the sidereal time was noted, should mark

* The

the ttig. 1 . correc ted time shewn by the sidereal clock, is technically calledkn°vyn sta ^ Scens * on °f tie Mid-Heaven. By means of the transits of^tertnined 5 ' ^ enor at, d rate of the clock (see pp. 104, 105, &c.) areduring t j le ' . k be clock so corrected, must shew at every point of time,*ny one ^ 5I< toreal day, the right ascension of a star, (should there bea point in the heavens then on the meridian.