FORMATION OF MOUNTAINS. 821 



beneath was that of the geosynclinal ; and lateral pressure, however 

 powerful, could not possibly have raised at the time the downward- 

 flexed crust. The pressing of the beds into a narrower space would 

 have given more or less of elevation to the upturned mass, as Le 

 Conte has remarked. 



One or more profound fractures and great faults are a feature of 

 the process, as recognized by Suess in his memoir on mountain-making, 

 and the profoundest is commonly to the rear of the axis, and not on 

 the shoving side. The greatest in the Green Mountains and in the 

 Appalachian range was on the western side, not on the eastern, or 

 shoving side. In the Sierra Nevada it appears to have been on the 

 east side, or, again, away from the ocean, this slope of the Sierra 

 being very steep compared with the western (p. 797). 



In the Juras, Apennines, Carpathians, and Alps, which have the 

 inequilateral features of the Appalachians, one side, as Suess observes, 

 " is the side of shoving and folding, the other of fracture, and, in the 

 Apennines, of volcanic phenomena." The fracture line of the Juras 

 is turned toward the Alps. " The western Alps repeat the same con- 

 trast of a folded outer side and an inner side of fracture, though here 

 the volcanic mountains are wanting." 



2. Character of the Mountain Range thus made. — The mountain 

 range, begun in a geosynclinal, and ending in a catastrophe of dis- 

 placement and upturning, is appropriately named a synclinorium, it 

 owing its origin to the progress of a geosynclinal. [The word is from 

 the Greek for synclinal, and opos, mountain.] 



The resulting mountain structures vary greatly ; but the process is 

 fitted to produce all variations ; for the gentlest and broadest flexures, 

 as well as the steepest and closest ; for joints and slaty cleavage ; for 

 fractures of the extremest kind, giving exit or not to floods of igneous 

 rock ; for breakings and crushings of strata of indefinite amount ; and 

 also, — since heat would be a certain result of the friction, and that 

 so derived would be added to heat from below (p. 718) — for meta- 

 morphism of every possible grade, from oxydation or deoxydation to 

 the making of silicates and diamonds, from the reddening and baking 

 of sandstones to the complete crystallization of strata, and even the 

 production of granite, either in veins or terranes, or as the axial core 

 of a mountain ridge. . 



Synclinorial ranges differ much as to the amount of disturbance, the 

 character and number of the ranges of folds, the existence of a 

 granitoid axis or not, and the occurrence among the attendant phe- 

 nomena of igneous eruptions or not. The Sierra Nevada is an ex- 

 ample of a single mountain mass, with a granite axis (p. 797). Its 

 volcanic phenomena are probably of later origin. The several areas 



