observed on the Rods on the Shores of Greece. 341 



stance, harder than limestone, of a shining blackish-brown, waxy 

 fracture, radiated, slightly translucent. It is found equally at 

 the surface of marbles, dolomites, and compact limestones. Its 

 brown colour contrasts in an evident manner with that of the 

 marbles, which afford no alteration at the point of contact. 



When we have carefully examined this part of the shore, we 

 cannot fail to compare it to certain bands or zones of limestone, 

 perforated with cavities almost cylindrical, but sinuous and ir- 

 regular, which we meet at great heights in the interior of conti- 

 nents. They only differ from the former by the destruction of 

 the little asperities and sharp ridges which the rubbing of allu- 

 vial matters, and the action of atmospheric agents, have doubt- 

 less destroyed. We shall be much more induced to acknow- 

 ledge in it the trace of ancient shores, as these cavities are al- 

 ways superficial, exist independently of the nature of the rock, 

 and accompany other incontestible proofs of the sojourning of 

 the sea. 



The White Zone. 



Continuing to ascend, we enter into a zone which the broken 

 waves could not have reached, unless in the form of fine rain 

 carried by the wind. It may be designated the lohite zone ; in- 

 deed all vegetation there terminates, the brown colour of the 

 lower zone having disappeared by degrees, and given place to 

 the white tint natural to the rocks. 



Everywhere the surfaces are unstained ; so that between the 

 part occupied by the marine vegetation, and that where the 

 lichens begin to appear, the first trace of terrestrial vegetation, 

 there is a zone entirely bare. It is divided in every direction 

 by very wide fissures, and, although far from being so deeply 

 decayed as the preceding zone, it exhibits such asperities that 

 it is difficult to walk over it, and above all to press the hand 

 upon it. 



The examination of the surface shews that it is everywhere 

 perforated with little rounded cavities, of various depths, but 

 which never exceed from six to eight millimetres. They are 

 hollowed from beneath ; the entire surface is covered with them, 

 but the greatest are always observed on the little lines of fissures. 

 It is important to remark, that these cavities are found as fre- 

 quently on the vertical faces as on the horizontal or inclined ; 



