178 Proceedings of the Royal Society of Victoria. 



of cleavage.^ He ascribes the finer material to the rubbing 

 together under great pressure of the opposite faces of the 

 "fissure," and the difference of direction from the cleavage he 

 regards as "probably the result of torsion in the sandstone." A 

 radial arrangement around the anticlines and synclines is noticed, 

 and the fact that movement has taken place on these lines is 

 seen by the notched boundary with the slate. One side of such 

 notches I noticed to be often parallel to the " Assuring." But at 

 the Golden Pyke Mine, where it and the cleavage are well 

 developed, I noticed no corresponding change of cleavage direc- 

 tion with the change of direction of the " Assuring " round the 

 anticline. 



An exactly similar arrangement is well marked at Ohewton, 

 with the same notched boundary of the slate. It is described by 

 Mr. T. S. Hall as jointing. I noticed it well dev'eloped at two 

 synclines between Chewton and the tunnel. Its strike is about 

 the direction of the syncline, and it is not affected in its radial 

 arrangement by the fact that the axial plane of one of these 

 synclines is considerably inclined. 



At another place in these cuttings similar lines were seen in a 

 direction more nearly horizontal than vertical. 



The same structure is probably referred to by the term 

 " oblique lamination," used by Mr. Norman Taylor in Quarter- 

 sheets 13 N.E. and S.E. I do not find it noticed on the other 

 ■Quarter-sheets. These surfaces, then, appear to have no constant 

 relation either to the cleavage or jointing. The finer material 

 on them might result from ci'ushing or from grinding, the 

 arrangement of the mica flakes being in the one case at right 

 angles to the pressure and in the other parallel to the motion. 

 But their discontinuity in most cases and their curved form, 

 sometimes pronounced, agree best with crushing under pressure. 

 Their regular arrangement at the anticlines and synclines, and 

 their variable development, both in direction and degree of 

 definiteness and continuity, seem more likely to be connected 

 with the distribution of the strain within the individual beds 

 than with the forces acting on the mass as a whole. If the 

 strata were being folded under the pressure of superincumbent 



I Report on Bendigo Gold Fields, No. II. 



