244 ANNALS NEW YORE ACADEMY OF SCIENCES 



basin is far out of proportion to its extent; the coal beds are of unusual 

 thickness, the plications and other disturbances are very complicated, and 

 the conditions observed there have been regarded as arguing strongly in 

 favor of the doctrine that coal beds have been formed from transported 

 vegetable matter. 



No elaborate description, such as that by Fayol of Commentry or that 

 by Gruner of Saint-fitienne, has appeared respecting the basin of Decaze- 

 ville; but several brief memoirs have been published, some of which are 

 important. Blavier in 1806 described the coal, which even then had been 

 opened at several localities; Cordier in 1809 made incidental reference to 

 the coal beds and expressed surprise at the irregularity of their occur- 

 rence; Dufrenoy in 1841 discussed the region somewhat in detail; Boisse 

 in 1870 differentiated the deposits and grouped them into two systems, 

 while suggesting that there may be three. Somewhat later, Grand' Eury 

 investigated the Coal Measures of this basin from the viewpoint of paleo- 

 botany and made correlations with other areas. 



The first systematic statement known to the writer was given by Ber- 

 geron^ at the reunion of the Geological Society in I'Allier. He recognized 

 three systems of deposits and described the method by which the basin 

 was filled and the coal beds formed, applying the doctrine of deltas as an- 

 nounced by Fayol in the preceding year. This paper was accompanied by 

 a preliminary map, showing the positions of three deltas. His memoir, 

 published in the following year, defined sharply the three systems of 

 rocks, to which the terms Auzits, Campagnac and Bourran were applied. 

 The conclusions throughout are the same as those in the earlier paper, of 

 which this is but an elaboration, in so far as it relates to the Decazeville 

 area. Three years later, the properties near the city of Decazeville passed 

 into the possession of the Compagnie de Commentry et Fourchambault, 

 and, under direction of M. Fayol, the engineers of that company began 

 careful researches throughout the basin, which still continue. 



In 1900, an extremely important memoir appeared,^ in which the au- 

 thors summed up the results of studies made by Jardel and Picandet and 

 their associate engineers, as complementary to the work done by Bergeron 

 prior to the consolidation of the properties. It explains the relations of 

 the three systems, the mode in which the basin was filled, the sources of 



1 J. Bergkron : "Note sur les bassins houillers de Gralssessac et de Decazeville," Bull. 

 Soc. G6ol. de Prance, 3me. Ser., t. xvi, p. 1032. This contains detailed reference to the 

 work of his predecessors. 



. "fitude du massif ancien situ6 an sud du Plateau central," Ann. des Scl. 



G60I., t. 22, p. 196. 



= J. Bergeron, (A) Jardel et Picandet. "fitude g^ologlque du bassin houlller de 

 Decazeville (Aveyron)," Bull. Soc. G60I. de France, 3me. Ser., t. xxviil, pp. 715-749, 

 map and plate of sections. 



