But since we have found field, room, and ample verge for the play of our forces in material realms, and have acquired mastery of the superb forces of nature, we have come to an era of peace. We can now use our forces and those of nature with as real a sense of dominion and mastery on material things, resulting in comfort, as formerly on our fellow-men, resulting in ruin. We now devote to the conquest of nature what we once devoted to the conquest of men. There is a fascination in looking on force and its results. Some men never stand in the presence of an engine in full play without a feeling of reverence, as if they stood in the presence of God--and they do. The turning to these forces is a characteristic of our age that makes it an age of adventure and discovery. The heart of equatorial Africa has been explored, and soon the poles will hold no undiscovered secrets. Among the great monuments of power the mountains stand supreme. All the cohesions, chemical affinities, affections of metals, liquids, and gases are in full play, and the measureless power of gravitation. And yet higher forces have chasmed, veined, infiltrated, disintegrated, molded, bent the rocky strata like sheets of paper, and lifted the whole mass miles in air as if it were a mere bubble of gas. The study of these powers is one of the fascinations of our time. Let me ask you to enjoy with me several of the greatest manifestations of force on this world of ours. THE MONTE ROSA Many of us in America know little of one of the great subjects of thought and endeavor in Europe. We are occasionally surprised by hearing that such a man fell into a crevasse, or that four men were killed on the Matterhorn, or five on the Lyskamm, and others elsewhere, and we wonder why they went there. The Alps are a great object of interest to all Europe. I have now before me a catalogue of 1,478 works on the Alps for sale by one bookseller. It seems incredible. In this list are over a dozen volumes describing different ascents of a single mountain, and that not the most difficult. There are publications of learned societies on geology, entomology, paleontology, botany, and one volume of _Philosophical and Religious Walks about Mont Blanc_. The geology of the Alps is a most perplexing problem. The summit of the Jungfrau, for example, consists of gneiss granite, but two masses of Jura limestone have been thrust into it, and their ends folded over.