To find the true place of each planet, at any hour when w: have ccca-fion to erett a figure, it cnly requires to turn to the J&p.taeowis for the planets' places at noon ; thole being found, note how many degrees or minutts they move in the zodiac by twelve o'olock the next day, or from noon the preceding day j and then, by the help of the foregoing table, ic will be fecn how many degrees,, minutes, or feconds, they move in an, hour. For example, fuppole a planet moves one degree ;n twenty-four hours, how far does it ¡nov; in one hour ? At the top of the firit column is the figure 1, and in the fame line of the fecond column is 2 minutes and 30 leconds; vvh:ch ihews, that, if a planet be twenty-four hours in moving one degree, i; then moves at the rate cf two minutes and ^o feconds in an hour. Or fuppole a planet only moves two minutes is twenty-four hours; look into the firfc column of the table, for the figure 2, oppofite, in the feccnd column, fland 5 feconds, which Ihevvs, that if a planet moves two minutes m twenty-four hours, it then movts cnly five feconds in an hour. Again, if a ptenet's diurnal morion be thirteen minutes, what is its hourly motion ? Lock into the firil column for 13, and oppofite is 32, 30 . vvhrcn indicates, that, if a planet moves thirteen rrinutcsii twenty-four hour,«, it moves thirty-two leconds and thirty thirds in an l?our. The fame rules hold good for the motions of ail the planets; i( muft, however, be carefully ohferved, that, if the diurnal motion of any planet be in degrees, then you muil enter the firll column of the table, under the denomination of degrees, and the fecond column with minutes and feconds; but, J the riuinal motion of the pianct be only in minutes, then you muil begin to reckon in the ftrft column only with minutes, and in the fecund column with feconds and thirds. This is indicated by the initial letters placed over each column, which fignify degrees or minutes in the firll column, and, in the fecond, degrees and minutes, minutes and feconds, lecenas arid thirds. Then luppofe a planet moves one degree and thirteen minutes in twenty-four hours, how far does it move in an hour ? Refer to the table, and fay,
One degree in 24 hours is 2 min. 30 fee. o thirds per hcur.
1 hirteen min. in 24 hours is o min. 32 lee. 30 thirds.
Anfwer 3 2 30
And thus any quantity of a planet's diurnal motion may be reduced to time in the fame manner.
Eut as no figure can be ejected without the help cf an Ephemeris, and tables to ihew the Sun's place in each cf the twelve ligns, unlets by entering into long and tedious calculations, I fhall therefore inlert in this place the two pages of White's Fphemeris for June, 1784, and the tables above-mentionea, with an explanation of tnc whole.
(COP Y.) W II I T E 's E P II E MER1S, fc-r June, 17S4. Ji'ne ha* XXX Diy9.
Full moon the 3J day, it 34 minutes pift / afternoon. Lalt quarter the 10L11 day, at 28 nrnutes pail 8 morning. New moon the 17th day, at 6 minutes paft 6 evening, f 11 ft quarter the 25th day, at 33 minuses paft 10 at night.
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