172 SEE— FURTHER RESEARCHES ON [April 24, 



through twenty miles of crust. — The peculiar position of the sea 

 bottom between a molten globe and the overlying ocean is such that 

 any disturbance of the bottom, as in a volcanic eruption, would 

 naturally excite our suspicions that the crust had leaked and brought 

 the water into contact with the underlying ball of fire. The situa- 

 tion of the overlying ocean, with the fire so close beneath, is much 

 the same as that of the water above the furnace of a boiler, in which 

 steam is developed ; and if one had the molten globe for a furnace 

 and the ocean for a reservoir of water, leakage would develop steam 

 on a grand scale, and give rise to mighty experiments exactly resem- 

 bling earthquakes and volcanic eruptions. Some of these disturb- 

 ances might take the form of uplifts of the crust into islands, 

 mountains and submarine volcanoes, others near the edges of the 

 sea would cause lava to push out under the land and raise the coasts. 



Now the Pacific Ocean is everywhere surrounded by high moun- 

 tains, as if the lava had been pushing out at the margins of the sea. 

 And throughout the interior a vast number of islands are raised up 

 in deep water, and every part of the ocean is from time to time dis- 

 turbed by terrible earthquakes. One must therefore admit that the 

 ocean has the aspect which might be expected to result from a leak- 

 age of the ocean bed. Moreover the Pacific is surrounded nearly 

 everywhere by volcanoes, which emit chiefly vapor of steam. If it 

 is shown that mountains are formed by earthquakes, chiefly in the 

 expulsion of lava under the land, and some of the mountains break 

 out into volcanoes, then there will obviously be a connection not 

 only between earthquakes and volcanoes, but also between the vapor 

 of steam emitted from these smoking mountains and that formed 

 under the ocean by the leakage of the bottom. 



It is this intimate connection between all the related phenomena 

 which tells so powerfully in favor of the view that the leakage of 

 the ocean takes place through a layer of rock twenty miles thick. 

 The height of the mountains and plateaus is but a small fraction 

 of the thickness of the crust, and movement in the underlying layers 

 therefore usually gets relief without breaking through. The crust 

 of the globe is thick enough to offer great resistance to uplift, so 

 that the steam saturated lava usually adjusts itself beneath without 

 a surface eruption. Yet where the crust is sharply upheaved as in 



