286 Description and Use of the

screw the nut of the quadrant of altitude idthe zenith, art. 192, lay its graduated edgeon the center of the planet, and it will shewin the horizon the azimuth or point of thecompass, on which the planet may then beviewed in the heavens ; the horary indexwill at the lame time point out the hour ofthe night. When the planet comes to thestrong brass meridian, the index will shewthe time of its passage over that celestialcircle; and at the western edge of the ho-rizon, the time of its setting will likewisebe obtained.

PROBLEM