282 6EOORAPHY AND ASTRONOMY. Set the frame of the globe truly horizontal or level ; turn the north pole to the sun ; move the meridian up and down in the notches till the axis cast no shadow ; for then it points exact- ly to the sun, and then the arch of the meridian between the pole and the horizon shews the sun's altitude. Problem XXX. " The latitude and day of the month being given, to find the hour of theday when the sun shines." Let the globe stand on a level, and the meridian due north and south ; rectify the globe for the latitude and for the sun's place; stick a needle perpendicular to the sun's place on the globe ; turn the globe till the needle point directly toward the sun, and cast no shadow; then will the index shew the hour of the day. I proceed now to shew some problems to be formedby the stars upon the heavenly globe. ProblemXXXI. " The place being given, to find what stars never rise or never set in that place." Rectify the globe for the latitude ; turn it round, and observe that such stars as do not go under the horizon dur- ing its whole revolution, do never set in the place given ; and such stars as rise not above the horizon of the globe during its whole revolution, they never rise in the place given, nor are ever seen by the inhabitants thereof : So the Little Bear, the Dragon, Cepheus, Cassiopea and the Great Bear, never set at London, andmany of the southern constellations never rise. Problem XXXII: " The place and day of the month being given, to represent the face and appearance of the hea- vens and shew the situation of all the fixed stars at any hour of the night." Set the globe exactly north and south ; rectify it for the latitude, and for the sun's place ; then turn the globe till the in- dex points to the given hour. Thus every star on the globewill exactly answer the appearance of the stars in the heavens; and you may see what stars are near or on the meridian, which are rising or setting, whichare on the east or west side of the hea- vens. Thus October 13th at 10 o'clock at night, the glorious constellation Orion will appear on the east side at London, the star Regelin the left knee (or foot) of Orion j ust above thehorizon, the three stars in his girdle a little higher, &c. This represents the face of the heavens at night, as problem XVIII, does in the day. Note, This problem is of excellent use to find out and know the several constellations, and the more remarkable stars in each constellation. Here follow several problems to find the hour of the night by stars. ProblemXXXIII. as Any star on the meridian being given to find the hourof the night." In order to find what stars are upon the meridian at any
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