279 GEOGRAPHY AND ASTRONOMY. will find the sun begins to be entirely above their horizon toward the end of taurus, or near the middle of May ; and if you turn the globe a little farther, the descending ecliptic will meet the meridian and horizon in the north at the 8th or 9th degree of leo, or about the beginning of August: Thus it appears that those Laplanders will have the sun at least two months above their horizon in summer, or two months of complete day-light. Problem XVII. " To find the sun's declination and right ascension any day in the year; suppose the twenty-first of May." Find out the sun's place for that day, or the beginning of the first degree of gemini on the ecliptic ; bring that point of the ecliptic to the meridian, and the degrees numbered on the meridian will shew the sun's declination, viz. 20 degrees northward. At the same time the place where the meridian cuts the equator will shew the right ascension of the sup, or its distance from thepoint aries on the equator, viz. 58 degrees. It is mark- ed usually in degrees on the globe ; if you would turn it into hours, divide it by 15, and it amounts to three hours ii which is 52 minutes. Note, That any star's declination and right ascen- sion are found the same way by bringing it to the meridian. Re- member the sun'sdeclination is always north in our summer half- yearfrom the 21st of March, and southward in our winter ball- year from the 23d of September. ProblemXVIII. " To rectify the globe for the sun's place, any day in the year, and thus torepresent the face of the heavens for that day." Bring the sun's place found on the ecliptic of the globe to the meridian ; and at the same time set the hour-index or pointer of the dial to the upper 12, that is, to noon. Note, When the globe is thus rectified for the latitude of the particular town or city by problem 7th, and for the zenith of it by problem 9th, and for the sun's place in the ecliptic that day by this problem 18th, it is then fitted to resolve most of the fol- lowing problems, for then it most exactly represents the real face and state of the heavens for that day. Here let it be observed, that this practice does really repre- sent the face of the heavens only for that day at noon, (when the astronomers day begins) and not for all the following hours ofthe day ; because the sun is every moment changing his place a little in the ecliptic. Rut it is customary, and it is sufficient for learners, to make this go for a representation of the heavens for all that day, to perform any common operations. Problem XIX. " The place and day being given, (viz. May 10th at London) to find at what hour the sun rises or
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