THE volcanic national parks are Lassen Volcanic, Crater Lake, Mount Rainier, Yellowstone, and Hawaii. Though several of them exhibit extremely high mountains, their scenic ensemble differs in almost all respects from that of the granite parks. The landscape tends to broad elevated surfaces and rolling hills, from which rise sharp towering cones or massive mountains whose irregular bulging knobs were formed by out-breaks of lava upon the sides of original central vents.
The Cascade Mountains in Washington, TOregon, and northern California are one of the best examples of such a landscape; from its low swelling summits rise at intervals the powerful master cones of Shasta, Rainier, Adams, Hood, Baker, and others. Fujiyama, the celebrated mountain of Japan, may be cited as a familiar example of the basic mountain form, the single-cone volcanic peak. Vesuvius is a familiar example of simple complication, the double-cone volcano, while Mauna Loa in Hawaii, including Kilauea of the pit of fire, a neighbor volcano which it has almost engulfed in its swollen bulk, well illustrates the volcano built up by outpourings of lava from vents broken through its sides. Flat and rolling Yellowstone with its geyser fields, is one of the best possible examples of a dead and much eroded volcanic region.
The scenic detail of the volcanic landscape is interesting and different from any other. Centuries and the elements create from lava a soil of great fertility. No forests and wild flowers excel those growing on the lavas of the Cascades, and the fertility of the Hawaiian Islands, which are entirely volcanic, is world-famous. Streams cut deep and often highly colored canyons in these broad lava lands, and wind and rain, while eroding valleys, often leave ornately modelled edifices of harder rock, and tall thin needles pointing to the zenith.
In the near neighborhood of the volcanoes, as well as on their sloping sides, are found lava formations of many strange and wonderful kinds. Hot springs and bubbling paint pots abound; and in the Yellow-stone National Park, geysers. Fields of fantastic, twisted shapes, masses suggesting heaps of tumbled ropes, upstanding spatter cones, caves arched with lava roofs, are a very few of the very many phenomena which the climber of a volcano encounters on his way. And at the top, broad, bowl-shaped craters, whose walls are sometimes many hundred feet deep, enclose, if the crater has long been dormant, sandy floors, from which, perhaps, small cinder cones arise. If the crater still is active, the adventurer’s experiences are limited only by his daring.
The entire region, in short, strikingly differs from any other of scenic kind.
Of the several processes of world-making, all of which are progressing to-day at normal speed, none is so thrilling as volcanism, because no other concentrates action into terms of human grasp. Lassen Peak’s eruption of a thousand cubic yards of lava in a few hours thrills us more than the Mississippi’s erosion of an average foot of her vast valley in a hundred thou-sand years; yet the latter is enormously the greater. The explosion of Mount Katmai, the rise and fall of Kilauea’s boiling lava, the playing of Yellowstone’s monster geysers, the spectacle of Mazama’s lake-filled crater, the steaming of the Cascade’s myriad bubbling springs, all make strong appeal to the imagination. They carry home the realization of mysterious, overwhelming power.
Lava is molten rock of excessively high temperature, which suddenly becomes released from the fearful pressures of earth’s interior. Hurled from volcanic vents, or gushing from cracks in the earth’s skin, it spreads rapidly over large neighborhoods, filling valleys and raising bulky rounded masses.
Often it is soft and frothy, like pumice. Even in its frequent glass forms, obsidian, for example, it easily disintegrates. There are as many kinds of lava as there are kinds of rock from which it is formed.
Volcanic scenery is by no means confined to what we call the volcanic national parks. Volcanoes were frequent in many parts of the continent. We meet their remnants unexpectedly among the granites of the Rockies and the Sierra, and the sedimentary rocks of the west and the southwest. Several of our national parks besides those prevailingly volcanic, and several of our most distinguished national monuments, exhibit interesting volcanic interludes.