20 
MUSEUM BULLETIN NO. 11. 
tinually climbing up one ridge and down into the next trough, 
the miniature valleys being often 50 to 100 feet across, and from 
20 to 50 feet high; another such area is on Crystal mountain 
to the east and northeast of Goat peak. In some places a parallel 
set of ridges will trend across a major crest line at a low angle. 
Such a case occurs upon Lake and Kloof ridges, where minor 
north-south ridges cross a major northeast crest line. The lava 
capped Nipple Mountain block is more irregular. 
Relative Relief. 
The highest points in the Nipple and Wallace Mountain 
blocks ascend to elevations of 5,675 and about 5,758 feet respect- 
ively, the high ridges of St. John, Lake ridge, and Crystal moun- 
tain vary from 4,600 to over 4,800 feet, maintaining even skylines. 
Another set of flat ridges occurs in nearly all the blocks close to 
the West Fork and on King Solomon mountain; these have 
an elevation of from 3,800 to about 4,100 feet. 
Regional Slopes. 
Along the ridges free from the lavas even crest lines are 
the rule. 
Figure 2, profile 3, is drawn along the high crest of the 
Wallace Mountain and St. John blocks. It shows the up-land 
surface dipping toward Beaver creek from both sides and also 
into the east-west depression occupied by Joan lake. For about 
5 miles on the top of St. John ridge the slope is not much over 
100 feet to the mile, and in places the ridge is practically fiat, 
but where it dips north into the Joan Lake basin, and south into 
the Beaver, the slope varies from 250 feet to 300 feet to the mile. 
Below the valley wall the profile is, of course, much steeper, but 
does not represent a part of the upland surface. The profile on 
Wallace mountain is not very regular, the slope from the top 
of the volcanic mesas at 5,500 feet being very abrupt, and the 
general slope for the first mile about 900 feet, then for a distance 
of 2 miles the ridge top is much flatter, varying from about 4,650 
to just over 4,900 feet in elevation. On Crystal mountain the 
