Thus the stars, in unchanging order, rise majestically above the horizon in the east, wend their way across the great expanse of sky above our heads, and disappear below the horizon in the west. It is only necessary to note the position of a particularly bright star or a conspicuous constellation lying near the horizon and then return after several hours have elapsed and again note its position in the sky to prove this general movement toward the west. This is an interesting experiment for it is often a surprise to people to hear that the stars of the heaven are constantly shifting their position throughout the hours. Each star has an individual pathway which describes an arc across the heavens, the exception to this being the circum polar stars which describe complete circles around a point north of the zenith. The center indicated by the curved pathways of the stars is called the Pole of the Heavens, and in the northern hemisphere this important location is marked by the North Star. The North Star, also called _Polaris_ or the Pole Star, lies almost directly above the north pole of the earth, and is located in the sky by the "pointers" on the bowl of the Big Dipper. [Figure 02] Since we cannot realize the whirling of the earth on its axis which causes the heavenly bodies to appear to pass in the opposite direction, it is the same to us as if the axis of the earth continued upward to Polaris, thus causing this star to seem to stand still, while all the other stars in the course of twenty-four hours seem to whirl in fixed orbits around it. "The earth in circling round the moving sun, Seems to give motion to the nearer stars, Bending the tracks they trace across the sky." This remarkable performance may be photographed on a clear, moonless night if a camera is properly focused on the North Star and left exposed in that position for two or three hours. The photograph thus obtained will consist of a series of circular trails around the central star. These are produced by the stars moving slowly over the plate in consequence of their changing positions,--just as if the stars instead of our own little world had really moved. This is what the ancient peoples believed and in the words of Aratus "the axis shifts not a whit, but unchanging is forever fixed, and in the midst of it holds the earth in equipoise, and wheels the heavens itself around." Since the stars were always in the same order with reference to one another, it was thought that perhaps these luminaries were the heads of golden nails which made the heavenly dome secure. Thus through their apparent immovability, they acquired the name of "fixed" stars, although this fixity has long since been disproved.