He answered: "If men were far enough along in their thought journey (for the evolution of the mental side of man is a journey in the world of thought), they would avoid such theories as that which ascribes a molten interior to the earth. Volcanoes are superficial. They are as a rule, when in activity but little blisters or excoriations upon the surface of the earth, although their underground connections may be extensive. Some of them are in a continual fret with frequent eruptions, others, like the one under consideration, awaken only after great periods of time. The entire surface of this globe has been or will be subject to volcanic action. The phenomenon is one of the steps in the world-making, matter-leveling process. When the deposit of substances that I have indicated, and of which much of the earth's interior is composed, the bases of salt, potash, and lime and clay is exhausted, there will be no further volcanic action from this cause, and in some places, this deposit has already disappeared, or is covered deeply by layers of earth that serve as a protection." "Is water, then, the universal cause of volcanoes?" "Water and air together cause most of them. The action of water and its vapor produces from metallic space dust, limestone, and clay soil, potash and soda salts. This perfectly rational and natural action must continue as long as there is water above, and free elementary bases in contact with the earth bubbles. Volcanoes, earthquakes, geysers, mud springs, and hot springs, are the natural result of that reaction. Mountains are thereby forming by upheavals from beneath, and the corresponding surface valleys are consequently filling up, either by the slow deposit of the matter from the saline water of hot springs, or by the sudden eruption of a new or presumably extinct volcano." "What would happen if a crevice in the bottom of the ocean should conduct the waters of the ocean into a deposit of metallic bases?" "That often occurs," was the reply; "a volcanic wave results, and a volcano may thus rise from the ocean's depths." "Is there any danger to the earth itself? May it not be riven into fragments from such a convulsion?" I hesitatingly questioned. "No; while the configuration of continents is continually being altered, each disturbance must be practically superficial, and of limited area." "But," I persisted, "the rigid, solid earth may be blown to fragments; in such convulsions a result like that seems not impossible." "You argue from an erroneous hypothesis. The earth is neither rigid nor solid."