On a Piece -of Chalk 93 



workers of the chipped flints of Hoxne or of Amiens are 

 to them, as they are to us, in point of antiquity. 



But, if we assign to these hoar relics of long-vanished 

 generations of men the greatest age that can possibly be 

 claimed for them, they are not older than the drift, or 5 

 boulder clay, which, in comparison with the chalk, is 

 but a very juvenile deposit. You need go no further 

 that your own sea-board for evidence of this fact. At 

 one of the most charming spots on the coast of Norfolk, 

 Cromer, you will see the boulder clay forming a vast 10 

 mass, which lies upon the chalk, and must consequently 

 have come into existence after it. Huge boulders of 

 chalk are, in fact, included in the clay, and have evi- 

 dently been brought to the position they now occupy, 

 by the same agency as that which has planted blocks of 15 

 syenite from Norway side by side with them. 



The chalk, then, Is certainly older than the boulder 

 clay. If you ask how much, I will again take you no 

 further than the same spot upon your own coasts for 

 evidence. I have spoken of the boulder clay and drift 20 

 as resting upon the chalk. That is not strictly true. 

 Interposed between the chalk and the drift is a compara- 

 tively insignificant layer, containing vegetable matter. 

 But that layer tells a wonderful history. It is full of 

 stumps of trees standing as they grew. Fir-trees are 25 

 there with their cones, and hazel-bushes with their nuts; 

 there stand the stools of oak and yew trees, beeches and 

 alders. Hence this stratum is appropriately called the 

 " forest-bed." 



It is obvious that the chalk must have been upheaved 30 

 and converted into dry land, before the timber trees 

 could grow upon it. As the bolls of some of these trees 

 are from two to three feet in diameter, it is no less clear 

 that the dry land thus formed remained in the same 



