330 ELEMENTARY GEOLOGY 
quently found elsewhere, the greatest belt of active 
cones extends along the western side of the two 
Americas, thence across the northern portion of the 
Pacific, along the Aleutian Islands, and southwards 
through the Japanese Islands to the East Indies, where 
they abound. Thus the Pacific Ocean is almost com- 
pletely enclosed within a line of volcanic cones. 
While the number of 
volcanoes that are now 
active is not great, if 
we include under this 
term those peaks that 
have been built by. vol- 
canic action, but are 
now extinct or dormant, 
Fre. 196. the number of cones 
Cone at summit of Vesuvius, built by erup- 
wraps is greatly increased. 
Thus at present there 
is not a volcanic cone in n the United States, authentically 
proved to have been in eruption in this century; but 
in the great Cordilleran region of the West, there are 
many hundreds of cones, quite perfect in form, yet 
not really active volcanoes (Fig. 198). The same is 
true of many of the midoceanic islands, such as the 
Azores, St. Helena, etc. Probably, also, many of the 
coral islands of the midocean are existing upon the tops 
of submerged volcanic peaks. 
