the rate of at least 400,000,000 miles per year, toward the northern quarter of the sky. The path pursued by the sun appears to be straight, although it may, in fact, be a curve so large that we are unable in the course of a lifetime, or many lifetimes, to detect its departure from a direct line. At any rate we know that, as the earth accompanies the sun, we are continually moving into new regions of space. It has been stated that many millions of stars are visible with telescopes—perhaps a hundred millions, or even more. The great majority of these are found in a broad irregular band, extending entirely round the sky, and called the Milky Way, or the Galaxy. To the naked eye the Milky Way appears as a softly shining baldric encircling the heavens, but the telescope shows that it consists of multitudes of faint stars, whose minuteness is probably mainly due to the immensity of their distance, although it may be partly a result of their relative lack of actual size, or luminosity. In many parts of the Milky Way the stars appear so crowded that they present the appearance of sparkling clouds. The photographs of these aggregations of stars in the Milky Way, made by Barnard, are marvellous beyond description. In the Milky Way, and sometimes outside it, there exist globular star-clusters, in which the stars seem so crowded toward the centre that it is impossible to separate them with a telescope, and the effect is that of a glistering ball made up of thousands of silvery particles, like a heap of microscopic thermometer bulbs in the sunshine. A famous cluster of this kind is found in the constellation Hercules. The Milky Way evidently has the form of a vast wreath, made up of many interlaced branches, some of which extend considerably beyond its mean borders. Within, this starry wreath space is relatively empty of stars, although some thousands do exist there, of which the sun is one. We are at present situated not very far from the centre of the opening within the ring or wreath, but the proper motion of the sun is carrying us across this comparatively open space, and in the course of time, if the direction of our motion does not change, we shall arrive at a point not far from its northern border. The Milky Way probably indicates the general plan on which the visible universe is constructed, or what has been called the architecture of the heavens, but we still know too little of this plan to be able to say exactly what it is.