618 STEVENSON— FORM ATIOX OF COAL BEDS. [November 3, 



tance of more than 60 miles. Lorie eite.s lielpaire pere, who says 

 that it is one to 3 or even 4.5 meters thick and that it rests mostly 

 on blue clay, though in some localities on fine sand. It is double 

 near Ostend, where the lower bed is black, compact, with roots of 

 reeds, while the upper bed contains no reeds but has woody fibers, 

 apparently roots of heath plants. The peat and its overlying clay 

 are sometimes continuous under the dunes and shore, as is also the 

 case on the island of Walcheren in Zeeland. Trees, rooted in the 

 subsoil, occur frequently in the peat. Belpaire fils says that the 

 thickness of the peat and that of the overl\ing clay vary from i to 

 3 meters and that the clay level is never above high tide. On the 

 left bank of the Escaut (Scheldt) as it flows from France across 

 Belgium the peat is almost a meter and a half thick, but the clay, 

 2 to 3 meters, decreases as it recedes from the river. Lorie says 

 that Rutot found a divided peat near Blankenberghe in Belgium. 

 Reference to Rutot's^^'"' publication shows that the section is 



Meters. 



1. Shore sand 2.30 



2. Gray sandy clay 0.60 



3. Gray sand, with bed of Cardium- midway i.io 



4. Pure peat 2.00 



5. Gray sand, slightly argillaceous 0.40 



6. Sandy clay 0.50 



7. Gray, argillaceous sand 2.50 



The peat underlies a marine sand and overlies a sand which is but 

 slightly argillaceous. 



In 1852, Harting, as cited by Lorie, discovered hard dry peat at 

 10 to 12 meters below the surface in Amsterdam. Ghyben followed 

 this eastward toward the Wecht river. For much of the distance, 

 it is covered with marine sand, but at that river it is covered with 

 the main mass of peat, constituting the boundary between the sandy 

 diluvium and the alluvial deposits. In later years it became possible 

 to confirm and to extend the early observations, for many borings 

 have been made along railroad lines within the polder areas of Hol- 

 land. Lorie has tabulated the records of 124 such borings, showing 



'^^A. Rutot, " Le puits artesien de Blankenberghe," Bull. Soc. Beige de 

 Geol., Vol. TI., 1888, Mem., p. 261. This author has given equally illustrative 

 records in later memoirs published in tjiis Bulletin, Vol. VIII.. 1894; Vol. 

 XL, 1897. 



216 



