ON NATIONAL GEOLOGICAL SURVEYS: EUROPE. 227 



The publication commenced in 1879 ; five sheets, in the neighbour- 

 hood of Helsingfors, were issued up to 1882. There are descriptions 

 ('Beskrifning') to the sheets. All the superficial deposits are shown. 



The explanations on the maps are given in Finnish and Swedish ; 

 the ' Beskrifning ' is in Swedish. 



The meridian is Helsingfors, 25° 12' E. of Greenwich. 



France. 

 Service de la Carte Geologique detaillee de la France (Paris). 



The origin of this survey may be traced to the Paris Exhibition of 

 1855, when, under the direction of Dufrenoy and Elie de Beaumont, 

 twenty maps (scale 1 : 80,000), were coloured geologically in MS. 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 1867. 



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

 surveys were in progress in neighbouring countries, led to the establish- 

 ment of the existing geological survey in 1868, with Elie de Beaumont 

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



The map employed is the ' Carte Topographique de l'Etat- 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, 259-267. It has 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 1,113. In addition to these many sub- 

 ordinate signs have been devised, further explaining or modifying the 

 others. 1 



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 16 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 67 sheets are issued 

 (to February 1885), chiefly in the north. 



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

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

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

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

 and the Loire. 



The. foregoing statements refer only to the existing survey, but 

 there were official publications of earlier date. 2 In 1822, incited thereto 



1 All these signs, &c, are fully explained in pamphlets issued in 1874, ' Generalites ' 

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



2 A notice of the various geological maps of France was given, by Professor 

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



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