MOUNTAINS 311 
mountain (Fig. 185), which, when newly formed, con- 
sists of upfolded rocks, with the strata dipping away 
on both sides of the highest part, just as the sides of 
a roof dip from the ridge-pole. Here also, but a single 
ridge results from one fold; but as such mountains 
are cut down by denudation, they are often divided 
into two ridges (Fig. 186), where some hard layer in 
each limb of the 
anticline protrudes. 
As the fold dies out, 
these ridges unite 
by a loop (Plate 14). 
Still further denuda- 
tion may bring the 
hard layers at the 
bottom of the syn- 
cline into sufficient 
relief to transfer the synclinal portion to a mountain, 
giving us what is then known as a synclinal mountain 
(Fig. 182). 
While the anticlinal fold may be symmetrical (Figs. 
182, 185, and 186), with uniform dip on either side 
of the axis,’ it is usually unsymmetrical (Figs. 187 and 
188). This may increase to such an extreme of com- 
plexity, that the folds become actually overturned. 
Fic. 185. 
Anticlinal mountain ridge. 
1 The axis of a fold is the line passing through the centre, and extending in 
the direction of greatest length of folding. 
