52 Mr HOPKINS, ON RESEARCHES IN PHYSICAL GEOLOGY. 



therefore an anticlinal line formed along one fissure, may easily be 

 conceived to be continued along another, not exactly in the same 

 line. If we conceive several transferences of this kind to take place 

 from one fissure to another, we shall have a discontinuous anticlinal 

 line, each portion of which will be as rectilinear as the fissure with 

 which it coincides; but if the physical structure of the mass should 

 be placed under that disguise so frequently spread over it by super- 

 ficial agencies, the geologist, instead of detecting this discontinuous 

 line, consisting of a number of straight ones having parallel directions, 

 will probably only recognize a somewhat ill defined anticlinal line of 

 irregular curvature, and apparently destitute, in a considerable degree, 

 of those characters of rectilinearity and parallelism with the general 

 axis of elevation which this theory might appear to assign to such 

 lines. It may also be observed, that since on the opposite sides of a 

 transverse fissure the movements of the adjoining masses will be in 

 some degree independent of each other, it is easy to conceive that 

 this cause also may sometimes facilitate the transference of an anti- 

 clinal line from one longitudinal fissure to another, and thus destroy 

 its apparent rectilinearity. 



Similar observations will equally apply to the directions of longi- 

 tudinal valleys, as far as their formation may be referrible to the causes 

 above mentioned. 



53. It has been stated how much the ultimate position of the dis- 

 located mass may generally depend on accidental causes. In particular 

 cases however, and especially with respect to those portions of the mass 

 adjoining the lateral boundaries of the general elevation, there appears 

 reason to expect that the phenomena would, according to our theory, 

 frequently follow a certain law. Suppose the diagram, page 51, to repre- 

 sent the portion of the mass bounded by two parallel transverse' fissures, 

 produced as described in Art. 43, by a greater intensity of the elevatory 

 force acting at the point C. For the greater simplicity, we may also 

 suppose this force to act symmetrically with respect to the two transverse 

 bounding fissures. Then, after the general elevation has proceeded as far 

 as represented in the diagram, page 45, and the fissures have been formed. 



