498 REVIEWS 
12. By continually injecting the land with lava from under the bed of the 
sea the coast is raised and the mountains upheaved, and some of them usually 
break out into volcanoes; while at the same time the support of the sea bottom 
is undermined by the thinning-out of the fluid substratum, and at intervals the 
bottom sinks down to restore stability. 
13. The sinking of the sea bottom in this natural process of earthquake 
injection of the land is the cause of that class of sea waves found to follow violent 
earthquakes, in which the water first withdraws from the shore and then returns 
as a huge wave. Those waves noticed to rise suddenly without previous reces- 
sion of the water usually are due to submarine upheavals and eruptions in the 
bed of the sea. 
14. Islands are built up by injection from the sea, and hence have their 
mountains as veritable backbones, because the injection is symmetrical from both 
sides. In many cases the sea bottom is thus undermined and finally sinks down, 
making a hole beside the island, or a trench. The fact that all islands are not ' 
accompanied by such sinks is no argument against the theory, because the sub- 
sidence has not always taken place; it is the occurrence of even a considerable 
number of such sinks beside islands which proves the validity of the theory: 
Such intimate associations between elevation and depression could not be the 
result of chance. 
15. In the repair of ocean cables broken by earthquakes, subsidence of the 
sea bottom is frequently found to follow these disturbances. This is a direct 
observation of the above effects in certain cases which are established by actual 
measurement, the subsidences frequently amounting to hundreds of fathoms. 
16. The sea bottom does not subside without the lava under the crust being 
forced out into some other place, as into islands, submarine ridges, or shores; 
none of this movement is due to the secular cooling of the earth, but is all to be 
explained by the undermining effect of steam accumulating under the earth’s 
crust. 
17. Mountains in the interior of a dry country, as the Rocky Mountains in 
Colorado, exhibit no important movements, while those on the coast, like the 
Andes, are always heaving. ‘This shows that the sea is the cause, and not the 
secular cooling of the globe, which is wholly insensible. 
18. The only countries which are free from earthquakes are the deserts, and 
therefore practically uninhabitable; there is accordingly no escape from earth- 
quakes, and buildings designed for permanency should be framed to withstand 
them without material injury. 
tg. While in the long run the elevation of the land predominates, there is 
also subsidence, due to the non-occurrence of the forces in certain regions beneath 
the crust. It is idle to deny these oscillatory movements of the crust, and many 
good illustrations of both are clearly established. Every island which is thrown 
up in the sea is a witness to one of the most general laws of nature. 
20. As water is taken up in the crust both in the crystallization of rocks and 
