rutnce sownno 1851.: ’

Duration-~--—----lh.44m. ‘ . ., A very small portion only of the Sun's Northern hmb Inll be! bscured. This Eclipse will be total and central in the norther . ' part of British America, Davis Straits, Greenland, lceland, Norway and Russia. .

_._ l

Venus will be the Morning Star until Octr. ll. Aftet' whicN. he will be the Evening Star to the end ofthe year. ' Mans will be the Morning Star during the year. ', Jenn-en will be the Jllorning Star until April 9, then thei Eocnin Star until Octr. 22, thence the Morning Star to the: lose 0 the your. e 3 SATURN will be the Evening Star until April l5. ,then the: Morning Star until Octr. 2‘2, after which the Evening Star. '

EXPLANATION OF THE CALENDAR PAGES. ' Ll" HAND rust. !

Column. l 1 ’& 2.—Contaln the days of the month and of the weeh. i 3 8t 4.—The rising and setting in mean time of the highest point, 011 V of the upper limb of the Sun, corrected for refraction. ' 5.—-Days length in hours and minutes. ' ; 8.—The Equation ofTime (or quantity by which the Sun is sloeoj

or fast of the clock) at noon, apparent time (not mean);

at Greenwich. The interval of time between the Sun being.

on the Meridian or Soothing, on one day and his being on}

the Maidian or Southing on the next day, is not alwayq'

the same; and therefore, solar days are not equal in dorm;

tion; about one-half are a little more, and about on.“

half are a little lens than 24 hours. A clock regu-x

lated by the Sun, or the Sun-dial. would need frequent:

adjustment; to avoid this, an imaginary sun is supposed tq’

more, so that the interval of time between its consecutive;

passages over the meridian is always the same, viz, 24

hours; such a time represents a mean solar day, and it i '

the average of all the apparent solar days in a year. The

difi'erence of time between the imaginary Sun and the true

Sun passing the Meridian, is called the “ Equation oil

'I'ima." the amount of which at noon on every day is

inserted in this column.. There are only 4 days in, the yean;

when apparent and meantime are the same, or the Equation

of time is nothing. In this year these days are April IGJ

June l6, Sept. I, and Deer. 25. l By the asuistance of the numbers in this column, a clock can be set by a Sun-dial as follows ;~—Whenfast is placed“ above the number opposite to the day, then the cloelnl ought to be set fast on the time shown by the Sun-dial—l and when slow is above the number, the clock ought to ' set so much slower. Ethple:—When the Sun show. noon on the Sun-dial on June I, and July I, what are the}