468 STEVENSON— INTERRELATIONS OF FOSSIL FUELS. 



tained Orthoceras, Lingula, Pernopecten and Carbonicola. Renier®* 

 states that this coal seam was covered by ocean water soon after 

 deposition, so that at some localities it has been replaced with dolo- 

 mite. This dolomite encloses the vegetable pulp of the swamp, little 

 changed. 



The mass of deposits decreases toward the east. Andenne from 

 340 to 170 meters; Chatelet, from 400 to 288; Charleroi is 1,270 in 

 Couchant de Mons but only 970 in the Liege district. Four coal 

 seams at most are in the Andenne ; the same number in the Chatelet, 

 but they are unimportant except in the Liege district ; Charleroi is 

 rich throughout, having 19 workable seams in Couchant de Mons 

 with 10.70 m. qf coal, 20 in Charleroi, with 16.85 ^-^ 23 in Liege 

 with 17.45 m. of coal. Flenu in Couchant de Mons has 45 seams 

 with 27.20 m. ; besides these, each more than 30 centimeters thick, 

 there are many veinettes, which rarely become thick enough for local 

 operation. 



Intervals between coal seams vary almost capriciously. Smey- 

 sters^^ notes many instances in the eastern part of Hainaut basin; 

 one may mention here only that between the Mere-de-Veines and 

 the Crevecoeur. This interval is usually 10 or 12 meters, but at 

 one locality, it is reduced to 60 cm., yet within a short distance the 

 normal interval was observed. The coal seams are equally variable 

 and some of them, as mentioned by Stainier, resemble a string of 

 huge beads. Several seams are persistent enough to be utilized as 

 horizons, but great variability characterizes all. 



Many years ago, Cornet''^ grouped the Belgian coals into (i) 

 houille maigre a longue flamme ou houille flenu; (2) houille maigre 

 a longue flamme ou demi-grasse; (3) houille grasse marechale ou 

 houille grasse ; (4) houille seche a courte flamme ou houille maigre. 

 ( I ) is brilliant, with conchoidal fracture, ignites readily, yields much 

 illuminating gas, but the coke is not well fused; (2) has shaly frac- 

 ture, often has fusain, yields excellent but not strong coke ; (3) gives 

 a coke good for all purposes ; while (4) burns slowly and the coke is 



6* A. Renier, " Les relations geologiques du Bassin houiller du Nord de 

 la France avec les gisements beiges," Bull. Asoc. Ing., Fasc. i, 1919, p. 18. 



^^ J. Smeysters, Ann. dcs Mines, t. V., 1900, pp. 103-106. 



°'^ F-L. Cornet, " La Belgique Minerale," Catalogue of Paris Exposition, 

 ■1878, Separate, pp. 18-25. 



