GEOLOGICAL SECTIONS. 57 



hollows in the chalk that have been made by rain-water 

 holding in solution carbonic acid, and which, percolating 

 through into a fissure, has increased the size of its pas- 

 sage by removal, as a bi-carbonate, of a portion of the 

 rock. At some former time the surface must have been 

 covered with a gravel ; these are its only relics here, 

 the bulk of the deposit having been removed by subse- 

 quent denudation. 



We are informed that the pit is forty feet deep, and 

 we approximately verify the statement by counting the 

 spaces between the layers of flint, which are, as nearly 

 as may be, six feet apart ; also that the lower part of 

 the chalk in the pit is that which is used for building. 

 On examination this proves to be somewhat harder 

 than the other portions, and it breaks up into larger 

 blocks; but, with the exception of a slightly yellow 

 tinge that it possesses, it is just the same in appearance. 

 Specimens of each kind are chipped out, to be taken 

 away with us, that they may be submitted to test and 

 experiment. 



The next proceeding is to select a suitable part of 

 one of the flint layers (in this case on the E. side of the 

 pit), to place our hammer-handle thereon in the same 

 line, and on this again the clinometer the angle of dip 

 reads 3, somewhere in a S. direction. Then we try to 

 get another observation at right angles, or nearly so, to 

 the first at the N. end without success, but on the S. 

 we are enabled to do so by removing some fallen rub- 

 bish. This reads 0, consequently the first observation 

 has given us the true dip of the beds, and the E. side 

 of the pit happens to have been cut in its direction. 

 We take this direction by compass-bearing, it proves to 



