If one knows nothing else of uranography, one should at least know Polaris, the “North Star.” To recognize that star is to be able to orient yourself wherever you may be in the northern hemisphere. A whole volume could be written on its connection with human affairs. For at least two thousand years it has been the cynosure of sailors, and of wanderers by land as well. You cannot be lost if you have Polaris to guide you. The magnetic compass varies and misleads, the sun and the moon change their places, all the other stars circle through the heavens, but Polaris is always there, shining over the pole of the earth, the image of steadfastness. Only the slow Precession of the Equinoxes affects it. At the present time it is within one degree and a quarter of the true pole of the heavens, and it is drawing nearer that point, so that in two hundred years it will be less than half a degree from it--less than the apparent diameter of the moon. The little circle that it daily describes in the sky may be disregarded, for it is hardly noticeable except with instruments; but it is easy to fix the star’s position with considerable accuracy by simple observation. Note that the Great Dipper and the “W”-shaped figure in Cassiopeia are on opposite sides of the pole. When one is above, the other is below; when one is on the east, the other is on the west. Draw an imaginary line from the star Mizar in the Great Dipper to the star Delta (δ) in Cassiopeia and it will pass almost directly through the pole. Polaris is on that line, a degree and a quarter from the pole in the direction of Delta Cassiopeiæ. If the observation is made when Delta is above the pole and Mizar below it, Polaris will be on the meridian, or north and south line, a degree and a quarter above the pole; when Delta is west of the pole and Mizar east of it, Polaris will be a degree and a quarter west of the meridian; when Delta is below the pole and Mizar above it, Polaris will be on the meridian a degree and a quarter below the pole; and, finally, when Delta is east of the pole and Mizar west of it, Polaris will be a degree and a quarter east of the meridian. The intermediate positions you can easily deduce for yourself.