specially remarkable that Michell should 

 have correctly applied to the strata be- 

 tween Grantham and Balderton the ap- 

 pellation of Lyas, a term not then known 

 or in use nearer than Gloucestershire or 

 Somersetshire, showing that this saga- 

 cious observer " had contemplated the 

 identity of the British strata over wide 

 spaces." 



Few men, unless they chance to be ex- 

 perienced field-geologists, can fully appre- 

 ciate the amount of time, skill and labour 

 which the construction of this Table of 

 Strata required. It must represent the 

 result of the journeys of many years over 

 a large part of the southern half of Eng- 

 land. It implies an infinite patience and 

 no little lithological deftness in correlat- 

 ing the petrographical characters of the 

 various strata, with such success as to be 

 able to identify the different members at 

 distant parts of their outcrop. The key 

 furnished by organic remains to the 

 chronological sequence of the formations 



67 



