This historic book may have numerous typos, missing text, images, or index. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. 1906. Not illustrated. Excerpt: ... work late at night or early in the morning, has the opportunity of seeing again all the features which he saw on the waxing moon, but this time with the shadows thrown the reverse way--under evening instead of under morning illumination. In fact the character of any formation cannot be truly appreciated until it has been carefully studied under the setting as well as under the rising and meridian sun. We must now turn our attention to the various types of formation which are to be found upon the moon. These may be roughly summarized as follows: (i) The great grey plains, commonly known as Maria, or seas; (2) the circular or approximately circular formations, known generally as the lunar craters, but divided by astronomers into a number of classes to which reference will be made later; (3) the mountain ranges, corresponding with more or less closeness to similar features on our own globe; (4) the clefts or rills; (5) the systems of bright rays, to which allusion has already been made. i. The Great Grey Plains.--These are, of course, the most conspicuous features of the lunar surface. A number of them can be easily seen with the naked eye; and, so viewed, they unite with the brighter portions to form that resemblance to a human face--' the man in the moon '--with which eyeryone is familiar. A field-glass or small telescope brings out their boundaries with distinctness, and suggests a likeness to our own terrestrial oceans and seas. Hence the name Maria, which was applied to them by the earlier astronomers, whose telescopes were not of sufficient power to reveal more than their broader outlines. But a comparatively small aperture is sufficient to dispel the idea that these plains have any right to the title of 'seas.' The smoothness which at first suggests...