Mount Adams therefore presents a greater variety of history, a more complex and fascinating problem for the student to unravel, than any of its neighbors. This interest extends to the district about it, a country of new lava flows covering much of the older surface. The same conditions mark the region surrounding the newer peak, St. Helens, thirty miles west. In each district, sheets of molten rock have been poured across an ancient and heavily forested land. Thus as we travel up the rich valleys leading from the Columbia to either peak, we meet everywhere the phenomena of vulcanism.
Climbers ascending from South Peak to Middle Peak on Mount Adams, with the "bergschrund" above Klickitat glacier on right. This central dome is about 500 feet higher than South Peak.
Mount Adams, seen from Happy Valley, south side. Elevation about 7,000 feet. Mazama glacier is on right.
The lava sheet flowing around or over a standing or fallen tree took a perfect impression of its trunk and bark. Thousands of these old tree casts are found near both Adams and St. Helens. Where the lava reached a watercourse, it flowed down in a deeper stream, a river of liquid rock. Lava is a poor conductor of heat; hence the stream cooled more quickly on the surface than below. Soon a crust was formed, like the ice over a creek in winter. Under it the lava flowed on and out, as the flood stopped, leaving a gallery or flume. Later flows filled the great drain again and again, adding new strata to its roof, floor and sides, and lessening its bore. Long after the outflows ceased, weathering by heat and frost broke openings here and there. Many of the flumes were choked with drift. But others, in the newer lava beds, may be explored for miles. It was from the lava caves of northern California that the Modoc Indians waged their famous war in the Seventies.
Mount Adams, from Snow-Plow Mountain, three miles southeast of the snow line; elevation 5,070 feet, overlooking the broad "park" country west of Hellroaring Canyon.
COPYRIGHT, S. C. SMITH