THE MOON.

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tremendous volcanic action. Such action appears to have beenin itself much more violent than any which the Earth hasexperienced, while the effects produced upon the Moon byany given explosion would be much greater than upon theEarth , owing to the smaller attraction of the force of gravityby which they would be restrained. It is certainly the case thatsuch disturbances seem to have been extraordinarily frequentupon the lunar surface. There is also much evidence of asuccession of eruptions, for in many places craters, or ring-mountains, are seen overlapping and interfering with oneanother in a way which proves that the origin of some musthave been anterior to that of those by which they have beendisturbed.

If this be so, the question naturally suggests itselfIs thereany evidence of the existence at the present time of volcanicenergy still in action upon the Moon ? Our answer is:—Thereis either none, or, if there be any, it is very slight. We have noincontestable observation of any such occurrence. Certain spotsupon the Moon , which appeared unusually brilliant to SchrOter,Madler, and others, may have lost some of their brilliancy.But it is most probable that they are spots which have apeculiar power of reflecting the Sun’s light, or (when theyhave been noticed in the dark part of the Moon ) the faint lightwhich the Earth reflects to it, and which, near to the time ofNew Moon , causes the appearance which is popularly knownas the New Moon in the Old Moon’s arms. This is muchmore likely than that they are volcanoes in active eruption.The absence, or almost entire absence, of any appreciableamount of atmosphere or water upon the Moon (to the proofsof which we shall presently allude) also makes it very difficultto conceive that volcanic action can continue.

In connection with this question, we ought, however, tomention that some fifteen years since a considerable amountof discussion took place as to a change which was supposedto have occurred in a crater named Linne.* There seemed to

* This crater is situated in the locality of a bright spot in Mr. Ruther-furd’s photograph, which may be seen in the midst of a darker regiona little way to the left of the lower part of the Apennines , and slightly