22 
MUSEUM BULLETIN NO. 11. 
face is much more irregular, being broken by volcanic intrusions 
and flows, and cut into by canyons. On King Solomon mountain 
there is a high spot on the northwest side ranging from 4,000 to 
4,200 feet, and a ridge on the southeast, 200 feet below (Plate 
III). The slope from Nipple and Ferroux mountains to the 
walls of Hall creek is from 750 to 1,000 feet to the mile. 
Local Sleep Slopes and Flat Areas. 
In detail the upland is broken up and contains local slopes 
which have no relation to the average interstream slopes given 
above. Although the average slopes are not steep, and wide 
stream troughs and basins like those of Lassie lake exist which 
are nearly flat, one is constantly coming upon hillsides from 50 
to 100 feet high which are steep enough to make climbing diffi- 
cult. These are not often shown on the topographic map unless 
the particular slope is more than 100 feet high. Such sharp slopes 
are found within all parts of what is here called the upland, not 
only far away from the canyons which fret the borders of an 
interfluve, but also close to them. For instance, one-half mile 
west of the lower end of Clark lake there is a hill face of Wallace 
limestone, most of it bare rock, about 40 feet high, the slope on 
which must be very nearly 30 degrees. Within the quartz- 
diorite and quartz monzonite areas such hill slopes are common. 
It is, however, within the Tertiary lavas that the most marked 
cliff faces are seen. Goat peak is surrounded by a sheer cliff 
wall over 275 feet high at its lowest point on the north side, and 
probably about 400 feet on the southwest. Sheer cliffs exist 
within every large patch of Tertiary extrusive on the map, 
whether such an extrusive patch lies in the middle of a flat up- 
land basin like the one between Lassie and Joan lakes or near the 
edge of a deep valley trough like that of Red Mountain valley. 
They lie near the contact of the extrusives with the older for- 
mations, as in the case of Goat peak, and the mesas to the 
northwest of it, or away from it, as does the cliff surrounding 
Nipple mountain. They vary in height from 20 to 200 or 400 
feet. 
A comparatively flat area lies partly within the quadrangle 
at its northeastern comer; it is about 4 miles wide, and covers 
