Ill 



from the front of escarpment, or, in the case of the Bunda 

 cliffs, a few hundred feet. 



Further east along the Bunda cliffs the top bed and its 

 underlying polyzoal limestone is perpendicular, or even over- 

 hanging, that part of the chalk within the influence of the 

 ocean swell being hollowed out. By the combined action of 

 percolating water from above and the sea waves below great 

 masses of the upper part of cliff are seen at short intervals 

 forming protecting buttresses to jutting points. The front of 

 the seawall is washed in all states of the tide, and follows a 

 curved line, the chords of which are about eight to ten miles 

 lona\ with subordinate serrations. On looking forward or 

 backward, as the case may be, one serration is seen projecting 

 beyond the one preceding it to the end of the long curve. 

 Each projection has a talus as remarked above, and the indent 

 between each is in length five or more hundred yards, but with 

 a long curve towards the east, and the shorter one directed 

 towards the west. 



This general appearance of the coast cliffs is modified at 

 places by the occurrence of slides of greater magnitude than 

 ordinarily. The first effects of the movement of the upper 

 beds on the chalk is visible on the smface in the form of long 

 crevasses parallel to the edge of the cliff, and at distances from 

 it of a few to many yards. 



The caverns, which are many on the Bunda Plateau, are 

 excavated in the crystalline limestone, and extend down into 

 the underlying friable band. Their presence is indicated on 

 the surface by crateriform depressions, in the centre of which 

 is the perpendicular aperture to roomy excavations, the roof 

 of which in many places rises nearly to the surface in the form 

 of inverted pot-holes. Though slight signs of waterflow from 

 the edge of the depression to the aperture are visible, yet in 

 the interior there is no indications of percolating water. The 

 earlier stages of the formation of the cavern are those perpen- 

 dicular vents called blow-holes, up which there rushes on hot 

 days a violent wind, which may also be heard coursing along 

 the lateral passages with the sound of a mill-race. From the 

 known widely-fissured and cavernous character of the crystal- 

 line limestone as seen on the coast, there can be little doubt 

 that the stratum throughout its whole extent presents con- 

 tinuous air passages. The air in the passages and caverns in 

 the interior part of the plateau acquires a higher temperature 

 during the day than that on the face of the sea cliffs, in conse- 

 quence of which an indraught is caused towards the hotter 

 region. On one occasion I compared the temperature of the 

 air as it flowed from a blow-hole with that in the shade of a 

 tree. The shade temperature was 78 deg., and the same ther- 



