“Very likely it was, if it depended upon the slow withdrawal of the atmosphere and water.”

“Good! Then again I am fairly well content, for all things must have an end. The most beautiful life finally merges into old age and death. I think I have read that some of your savants predict that the earth will not always be a living world. All that I ask is that you leave room somewhere in your lunar history for an age of life on the moon.”

“Very well then. As I have told you several times, Science does not positively forbid you to picture such an age if you will. She only says that she cannot find the evidences of its existence. Still, as we are going to see later, there are those who think that they can perceive indications of some simple forms of life on the moon even now. I will grant you that in the past these may have been more numerous and more highly organized.”

By this time the afternoon had waned and the trees were lengthening their shadows upon the lawns of the park.

“Perhaps,” I said, “we had better postpone an examination of the remaining photographs of the series exhibiting the moon’s various phases until after dinner. They will show very well in the light of the electric chandelier. I have but a few words to add concerning the rays of Tycho. The opinion of Nasmyth concerning their mode of origin has not been universally accepted. Prof. William H. Pickering, for instance, has suggested that the rays are formed by some whitish deposit from the emanations blown out of comparatively minute craters lying in rows. He supposes large quantities of gas and steam given forth from craters surrounding the rim of Tycho, and, in consequence of these gases and vapors being absorbed and condensed in more distant regions, a wind constantly blowing away from Tycho and distributing the white deposit in windrows. A similar explanation has been applied to the shorter and more irregular systems of rays surrounding Copernicus, and a few other ring mountains.”

“I prefer the Nasmyth hypothesis,” said my friend, as we rose and took the path to the house. “It is, to be sure, more gigantically tragic, but then it is simpler and more easily comprehended.”


III

FULL MOON TO OLD MOON