ON NATIONAL GEOLOGICAL SUUVEY8 : — EUnOPE. 



227 



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 stion 

 A. 

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 viglit- 

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,dcs of 

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The publication comraencod in 1879 ; five shoots, in the neighbour- 

 hood of llelsingfors, were issued up to 1H82. There are deHcriptions 



rvcy 



13 



volume 

 11' series 



been m 



resident. 



de Vin- 

 n<Tuishecl 

 ided ' par 



18 -were 

 the same 



i,r ordre du 

 jiont from 

 [was made 



|ap. This 

 ardennais 



prepared 

 vols. 8vo. 



loOO, show- 

 led in 1B77 



('Beskrifning') to the sheets. All the suporticial do]K)sits are shown. 

 The explanations on the maps are given in Finnish and Swodi 



cplanations on the maps 

 the ' Beskrifning ' is in Swedish, 



The meridian is Holsingfors, 2')'' 12' K. of Greenwich. 



ish; 



France. 

 Sendee de hi Carte Gcologlipie detail Ice de la France (Paris). 



The origin of this survey may bo traced to tho Paris Exhibition of 

 1855, when, under tho direction of Dufrenoy and PAio do Beaumont, 

 twenty maps (scale 1 : 80,000), wore coloured geologically in AIS. and 

 exhibited. These maps, with others, amounting in all to about sixty, all 

 in the N. and N.W, of France, were again presented at the Paris Exhibi- 

 tion of 18G7. 



The recognition of tho value of such maps, and the fact that similar 

 surveys were in progress in neighbouring countries, led^ to tho establish- 

 ment of the existing geological survey in 18G8, with Elie de Beaumont 

 as director. On his death, in 1875, M. Jacquot became director. 



The map employed is the ' Carte Topographicjue do I'fitat- Major,' scale 

 1 : 80,000. The meridian is Paris, 2° 20' E. of Greenwich. The map 

 of France is in 258 sheets; Corsica in sheets, 25U-267. It ha? hill- 

 shading without contours ; heights in metres. 



Each map is accompanied by an ' Explication ' printed on one side 

 only, to be attached to the map if desired ; some sheets also by plates 

 containing longitudinal and vertical sections and photographs. 



A very elaborate system of signs has been employed on the maps, for 

 distinguishing minute varieties of rocks, soils, ores, mineral springs, &c. 

 The number of these signs is 1,11.3. In addition to these many sub- 

 ordinate signs have been devised, further explaining or modifying the 

 others.' 



As the work progresses it will be reduced and published on the scale 

 of 1 : 320,000 ; this will be in 32 sheets ; Corsica in sheet 33. Each 

 sheet of this map will include IG sheets of the larger scale. 



The publication of the maps commenced in 1873, with sheet 48, Paris ; 

 the explanation of this being ' Cahier I.' About 07 sheets are issued 

 (to February 1885), chiefly in the north. 



In addition to the explanations of sheets there are ' Memoires ' ; No. 1, 

 ' Pays de Bray,* by De Lapparent, was published in 1873 ; No. 2, ' Minera- 

 logie IMicrographique,' by Fouque and Levy, in 1879. There are also 

 special monographs on the coalfields — Brioude and Brassac, Langeac, 

 and the Loire. 



''idhivms) 



lent of the 

 Sector being 



The foregoing statements refer only to the existing survey, but 

 there were official publications of earlier date.'^ In 1822, incited thereto 



' All these signs, &c., are fully explained in pamphlets issued in 1874, ' Generalitcs ' 

 A, B, C, and D. See also De Chancourtois, Ann. Mines, ser. 7, t. v. 1878. 



' A notice of the various geological maps of iVance was given, by Professor 

 G. A. Lebour, in the GioyrapMcal Magazine, vol. iii.p. 47, 1876. 



Q2 



