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25 Horizon. Mind the ame rule with all the fixed Stars, (but the Moon), and the wiftet of the Planets will require a reduction in their places in this Problem.

Problem 18. To find at what hour a Star ries on any day, uppoe Oct. 14th. What time doth the Bull's Eye rie?——Bring the Star to the Horizon, and ee what hour and minute points to the day propoed, and it is found to be 12 minutes before Eight at night, and ets 12 minutes before Ten in the morning.

Problem. 19. To learn to know the Stars by ight, at any hour, by the help of the Planisphere. Suppose July 20th. at 10h &c. P. M. you are out of doors, and rectify the Planisphere to that hour; then uppose yourelf to tand under that part of the heavens where is marked the Zenith of London in the Planisphere, and you will ee the Dragon's Head in the Vertex, Lyra South by Eat, the Stars of Pegasus nearly Eat, with from ten to twenty degrees of Altitude, the Great Bear Wet North Wet; Arcturus Wet South Wet; the Virgin's Spike nearly etting Wet-South-Wet; Cor-Scorpio South-South-Wet; Atair in the Eagle South-South Eat; Perseus and Capella near the northern Horizon; and you may ee the names of the ret in the Planisphere, that are then above the Horizon; and by varying the time of the year in your obervation, you will eaily ee, and learn the names of them all.—This is a ueful Problem, and hould often be repeated.