102 Prof. Judd — The Earliest Engraved Geological Maps. 



This very important work, which was issued by Gary on July 15, 

 1817, iUustrates in a remarkable manner the clearness of Smith's 

 views regarding both the underground structure of the country and 

 the relations of the forms of the surface produced by denudation to 

 that structure. 



In May, 1819, there appeared seven other geological sections 

 by William Smith, illustrating the structure of various parts of 

 England, viz. : (1) From London to Brighton through Lewes ; 

 (2) through Dorsetshire and Somersetshire to Taunton ; (3) through 

 Hampshire and Wiltshire to Bath ; (4) through Norfolk (Yarmouth 

 to Lynn); (5) through Suffolk to Ely; (6) through Essex and 

 Hertfordshire ; and (7) between London and Cambridge. In all 

 these sections the relations of the strata with the forms and altitudes 

 of the hills are well illustrated, the only points open to serious 

 criticism being the representation of the relations of the London 

 Clay to the strata above and below it, and the nature and succession 

 of the Wealden beds. 



In this same year, 1819, William Smith commenced the 

 publication of his " New Geological Atlas of England and 

 Wales," a work which, like so many of his undertakings, was 

 unfortunately left unfinished. Two parts of this Atlas appeared 

 in the year named : the first, containing Norfolk, Kent, Wilts, 

 and Sussex, being dated January 1st ; and the second, containing 

 Gloucester, Berks, Surrey, and Suffolk, bearing the date of 

 September 1st. In fulness of detail these county maps are far 

 superior to the corresponding portions of the map of 1815, and they 

 exhibit in not a few cases evidences of great advances in Smith's 

 knowledge. 



It was on November 1st of the same year that Greenough's 

 Geological Map of England and Wales made its appearance. 

 A glance at this map will show that in many respects it exhibits 

 considerable advances in geological cartography as compared with 

 Smith's map of 1815, or even with the later county maps. But 

 it must be remembered, as already pointed out, that the work 

 was really based on that of Smith, that for the Tertiary formations 

 and the strata below the Chalk Greenough had the invaluable 

 collaboration of Thomas Webster (who engraved the map), and that 

 for all the other parts of the country many of the Fellows of the 

 Geological Society supplied numerous very valuable contributions. 



On February 1st, 1820, there appeared the third part of Smith's 

 Atlas, containing the Maps of Oxford, Bucks, Bedford, and Essex ; 

 and in the same year Gary, who published all Smith's maps, issued 

 a "New Geological Map of England and Wales, reduced from 

 Smith's Large Map, for those commencing the Study of Geology." 

 This map does not differ in any essential feature from the map 

 of 1815, from which it was reduced. The scale of the map is 

 nearly the same as that of a reduction of the Greenough Map, 

 published in 1826 by J. Gardner ; and this latter map has been 

 frequently though erroneously ascribed to William Smith. 



In the following year (1821) appeared the fourth part of the 



