Mount Rainier and Mount St. Helens
ca.1841-1844
with reference to:
Presumably an Eruption of Mount St. Helens
sometime late 1700s to early 1800s
[p.640-641]
... Many a frosted peak stands to attest the former activity of volcanic fires in Oregon. Baker, Rainier, St. Helen's, Hood, and others of the series, have been partially described. These isolated cones so resemble the lofty summits of Mexico, that we cannot doubt, although they have not been ascended, that they once formed a line of volcanoes through the whole extent of Oregon, and far into California. It is reported that St. Helen's and Rainier have shown evidences of action within the three or four years past, * and an account is on record of ashes falling fifty years since. But these centres have not been the sole or even the principal sources of eruption. There are craters in the Coast Range, and others over the interior section. Mount Swalalahos south-southeast of Astoria is one of the former; sveral summits beyond Fort Hall are among the latter; and many peaks may be added to the number when the country is fully expolored. But besides these vents, there have been still wider eruptions from fissures over the country, near the paeks and subordiante to them as well in more distant regions, and from this source extensive beds of basalt or basaltic lava have flowed throughout the land. We have shown, in another place, that fissure eruptions are common in all volcanic regions, (at least in recent periods,) and the same fact is sustained by a survey of Oregon. ...
* Fremont mentions that on the 23d of November, 1842, ashes were ejected by St. Helen's. -- Rep. Exp. ii. 1842, '43, '44, p.193.
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Digital version of Dana's "United States Exploring Expedition - Geology"
was found at the Smithsonian Institution Libraries Website (2007).
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