Dr. Fitton's Notes on the History of English Geology. 4-49 



twenty years before its publication ; and this is the more ex- 

 traordinary, as vertical sections, detailing the order of the 

 beds, accompany the maps. Some of the copies, which we have 

 seen, — in which the characters expressinc; the predominant 

 mineral substances are coloured, — approach so near to the 

 expressive power of the modern geological maps of stratified 

 countries, that one is surprised that the authors did not, bj' 

 advancing this step, give that connexion to their results, which 

 is the essence of geology. 



It is not a little remarkable that De Saussuhe, who pub- 

 lished some years after the appearance of Monnet's atlas, and 

 must have been acquainted with that work, as well as with 

 the maps of the German school*, does not appear to have 

 attempted any geological map of the tracts he lias described. 

 Had he made that trial, it is probable that he would have an- 

 ticipated some of the important results which have since been 

 afforded by the maps and sections of the Alps, by Ebel and 

 Escherf. 



We have not yet seen the maps referred to by the late 

 M. Desmarest, as intended to be annexed to the Encyclo- 

 pedie Methodique ; but this writer judiciously insists on the 

 benefit arising even from attempts to express in maps tlie re- 

 sults of geological investigation ; and on the advantage of com- 

 bining with them vertical sections of the tracts represented. 



Some of the geological maps in colours, of the older Ger- 

 man mineralogists, are valuable; but the best plan, — which Mr. 

 Jameson has informed us, was devised, or much improved, by 

 Werner:j:, — is that of representing the several formations in 

 distinct but sober hues, and marking the superior rock by a 

 narrow band of deeper colour along the line of its contact with 

 the subjacent one; and this is nearly the method which is em- 

 ployed by English geologists at present. 



Of the county surveys, published by the Board of Agricul- 

 ture in 1794, five only have maps which indicate the compo- 

 sition of the surface ; and of these, that of Devonshire alone has 

 any pretension to geological distinction, — enumerating dun- 

 stone and limestone in its list of ' Soil.' — The remaining four, 

 Lancashire, Lincolnshire, Sussex, and Wiltshire, represent 

 by colours the superficial soils, in the agricultural sense of the 

 term ; — the first two distinguishing also the coal tracts. But 



• The four volumes (4th edition) of De Saussure's Voyages dans Ics Alpes, 

 arc dated respectively,— 1. 1779 ; II. 1786; III. and IV. 170«. 



t Ubcr der Bail der Erde in dem Alpcn Gebirge. II. Tom. 8vo. Ziirich, 

 1808. 



% Transactions of the Wemerian Society, vol. i. p. 149. 



Third Series. Vol. 1. No. 6. Dec. 1832. 3 M 



