WILLIAM SMITH : HIS MAPS AND MEMOIRS 
161 
I have not be able to trace a copy dated 1819, and fancy Phillips must 
have made a mistake of a year in the date, especially as he makes no 
mention of the map of 1820, referred to below. 
SMITH'S MAP OF 1820. 
A map in my possession not definitely referred to by Judd in his 
account of Smith's pubHshed maps, is entitled : "A New / Geological 
Map / of / England and Wales, / with the Inland Navigations ; / 
EXHIBITING / The Districts of Coal / and other sites of Mineral 
Tonnage / by W. Smith, Engineer, / 1820. / London : Pubhshed by 
J. Gary, 86 St. James's Str., Mar. 18, 1820." 
The map measures 24 inches by 29J inches, the scale being 15 
miles to the inch. The colours are more clearly indicated than in the 
large map, and the dividing lines between one stratum and another 
are much clearer. 
The following " Explanation of the Colours," in two columns, 
is given at the bottom of the map, and contains additional informa- 
tion to that supplied on Smith's large map of five years earlier, upon 
which, of course, this one is based* : — 
a London Clay, forming detached hills in the Environs of Lon- 
don I I 
h Brick Earth and Clay, interspersed tvith Sand and Gravel — 
The lighter shade of hrown sheivs the sandy districts which 
form extensive heaths ... ... ... ... | | 
c Chalk, the upper beds of which are soft and contain flinty Nodules 
The under beds with few Flints — soinetitnes used as a 
Building Stone At the foot of the Chalk is the Green Sand 
in which is found the Fire-Stone. Golt Brickearth be- 
neath I I 
d Sand of the Portland Kock, locally containing a Limestone, 
ih( first Quarry Stone, in the Series of English Strata, varying 
much in Quality, as at Portland, Purbeck, Chilmark, 
Swindon, Shotover, the Vicinity of Aylesbury, and Maid- 
stone in Kent I I 
* The colours are given in the tablets at the end of the description 
of each bed. 
