INTRODUCTION. Ill 



excellently printed detail-maps of fifteen counties. These 

 maps were on such a large scale, and so full of details, that 

 they had a limited circulation. Smith therefore conceived a 

 plan to publish a geological map of England and Wales on a 

 small scale, that should show accurately the course of the 

 surface outcrop of each stratigraphical horizon, and should be 

 accompanied by geological sections to the true scale of the 

 map. The preliminary sketch of this plan was drawn up in 

 1 80 1, and may be seen in the Archives of the Geological 

 Society; but it was 1812 before Smith found a publisher to 

 undertake the map. In 1815, the famous map of England 

 and Wales appeared, consisting of fifteen sheets in the scale 

 of i inch to 5 miles. The complete map is 8 ft. 9 in. high 

 and 6 ft. 2 in. broad. The individual strata are indicated 

 by different colours, and sometimes the basis of a stratum is 

 marked by a darker line of the ground colour. 



Smith's map is the first attempt to represent on a large 

 scale the geological relations of any extensive tract of ground 

 in Europe. It was a magnificent achievement, and was the 

 model of all subsequent geological maps. For English 

 geology, the publication of the map was the starting-point of 

 a new regime. Smith gave an explanatory text of fifty 

 pages, in which he introduced a stratigraphical terminology 

 adopted from the local names in practical use (Lias, Forest- 

 Marble, Cornbrash, Coralrag, Portland Rock, London Clay, 

 etc.), and these names of horizons have for the most part been 

 retained in geology to the present day. 



Between 1816 and 1819, Smith began a work entitled 

 Strata identified by Organised Fossils, containing prints of the 

 most characteristic specimens in each stratum. Four volumes 

 appeared containing the description of sixteen strata and 

 their characteristic fossils, from the horizon of Fuller's Earth 

 to London Clay, but the work was never completed. In 1817 

 he prepared an ideal geological section across England from 

 London to Snowdon, and the section was afterwards intro- 

 duced into most text-books. A contemporaneous account of 

 Smith's results and his terminology was published in 1818 in 

 a small book written by William Phillips. 



William Smith was a self-taught genius of rare originality 

 and with exceptionally keen powers of observation. Without 

 much intellectual cultivation, without any introductory 

 teaching, without any means at his disposal, and at first even 



