The Mountaineer Age 
longer. In ascending from the south it is necessary to go up 
the North Fork of Lewis river to a point opposite the moun- 
tain and then travel for several miles before beginnine the 
actual ascent. The great majority of visitors to the mountain 
leave the railway at Castle Rock and go by a good highway 46 
miles to a camp at Spirit Lake. The trip may be made by team 
in a day, or by an automobile in a shorter time. During the 
summer good accommodations may be had at Spirit Lake, 
which is at the very foot of the mountain on the north side. 
In making the aseent from Spirit Lake the trail leads 
through the forest for three miles, until the real foot of the 
mountain is reached, which coincides rather closely with the 
timber line. In other words the sparse growth of timber 
fails about the point where the steep climbing begins. The 
park-like nature of the forest, as timberline is approached, 
gives a touch of rare beauty to the region. <A circuit of the 
whole mountain at about timberline or a little below looks 
very inviting and could probably be made without mueh diffi- 
eulty. 
St. Helens in most respects is a typical voleano, and it 
affords an excellent opportunity to see and study vuleanism. 
Its eruptions seem to have all been approximately from one 
opening and hence the symmetry of the cone is conspicuous. 
There are many evidences of very late eruptions and erosion 
has made but little progress in the destruction of the mountain. 
The erupted matter seems to be confined almost wholly 
to two classes of material; viz., lava and pumice. The lava is 
far and away in excess over the pumice and makes up the great 
bulk of the cone. The lava rock is mainly andesite, with 
occasionally some basalt. The andesite usually contains some 
small erystals and varies in color from gray to red. The 
basalt is always black, except for the small white erystals of 
feldspar which may often be seen with the naked eye. It was 
not until late in the history of the voleano that explosive ac- 
tion gave rise to large amounts of pumice which were ejected 
from the crater. At the present time the northern slopes of St. 
Helens are covered with fragments of pumice which have ae- 
cumulated to the depth of many feet. In ascending the moun- 
tain on this side the route for much of the way is over the soft 
pumice rock which makes the climbing very laborious. In the 
ejection of the pumice much of it was thrown high in the air 
