iv 
PREFACE. 
menon of a reversal of the strata appears, for the 
grauwacke and limestone near the sienite are bent 
backwards, but at a farther distance the disturbance 
not having been so great, the strata incline towards 
the west, the subordinate bed of the " Wenlock and 
Dudley limestone" dipping beneath the exterior and 
upper zone of " Ludlow rocks." This explanation 
will render the account of our Geology given in the 
succeeding pages more intelligible and complete, and 
give additional interest to the map. 
