We will now notice some other explanations of volcanic action which have obtained a certain credence. First, we may note the view that these ejections from craters are forced out from a supposed liquid interior of the earth. One of the difficulties of this view is that we do not know that the earth's central parts are fluid--in fact, many considerations indicate that such is not the case. Next, we observe that we not infrequently find two craters, each containing fluid lava, with the fluid standing at differences of height of several thousand feet, although the cones are situated very near each other. If these lavas came from a common internal reservoir, the principles which control the action of fluids would cause the lavas to be at the same elevation. Moreover, this view does not provide any explanation of the fact that volcanoes are in some way connected with actions which go on on the floors of great water basins. There is every reason to believe that the fractures in the rocks under the land are as numerous and deep-going as those beneath the sea. If it were a mere question of access to a fluid interior, volcanoes should be equally distributed on land and sea floors. Last of all, this explanation in no wise accounts for the intermixture of water with the fluid rock. We can not well believe that water could have formed a part of the deeper earth in the old days of original igneous fusion. In that time the water must have been all above the earth in the vaporous state. Another supposition somewhat akin to that mentioned is that the water of the seas finds its way down through crevices beneath the floors of the ocean, and, there coming in contact with an internal molten mass, is converted into steam, which, along with the fluid rock, escapes from the volcanic vent. In addition to the objections urged to the preceding view, we may say concerning this that the lava, if it came forth under these circumstances, would emerge by the short way, that by which the water went down, and not by the longer road, by which it may be discharged ten thousand feet or more above the level of the sea. The foregoing general account of volcanic action should properly be followed by some account of what takes place in characteristic eruptions. This history of these matters is so ample that it would require the space of a great encyclopaedia to contain them. We shall therefore be able to make only certain selections which may serve to illustrate the more important facts.