( 110 ) 



Before continuing, I will add some remarks. The old surfaces, 

 observed by Dr. van Cappelle, prove nothing else but die fact that 

 in the formation of this sand periods of rest have existed, in which 

 organic life could develop on the sand. But this fact does not yet 

 prove that two different geological periods are necessary. Indeed 

 Dr. van Cappelle himself says that the vegetable beds lie between 

 the sand in the shape of wedge and so are very local. They have 

 not any value for a further determination of the age. I agree per- 

 fectly well with Dr. van Cappelle where he says on page 451: 



"this author (Dr. .1. .Martin at Oldenburg) will not believe that 

 the interglacial period has passed without leaving behind traces in 

 our country, though a convincing proof is not to be given, because 

 the ground moraine of the second glacier fails", and indeed it is 

 not to be thought otherwise that among our so-called postglacial 

 formations, deposits exist which are equivalent to such of the 

 second interglacial period and the third glacial period in Germany, 

 Imt a decisive proof is not to be given. Old surfaces between the 

 sand have not the least demonstrative power in this matter. To show 

 the point of view of Dr. van Cappelle in 1899 in regard to the 

 origin of the "heidezand", 1 will cite the conclusion at the end of 

 the mentioned communication: 



The "heidezand" has been formed in part by the melting waters 

 of the retiring tirst glacier, in part after the interglacial period by 

 the brooks which were streaming from the gravelhills in the time 

 of the approaching of the second glacier ; also the alluvial period 

 has contributed to the increase of the "heidezand" by the washing 

 of the hills." 



Dr. J. Lorie has laid stress upon the fact that the sandy plains 

 which accompany our great rivers and many smaller ones ought to 

 be considered as river-beds of the diluvial times. This sand has been 

 washed away from the banks and removed down the current. Two 

 examples will do. 



Ai the 4 th Physical and Medical Congress in 1893 (Transactions 

 page 393) Dr. Lomé speaks about "the peat-moors of Brabant- 

 Limburg." The speaker demonstrates that these moors owe their origin 

 to existing grooves in the surface which had no drainage. Those 

 grooves represent old branches of theMeuse. This whole region ought 

 to be considered as a diluvial delta of the Mouse. 



"From the stadium of the "wild waters'' when the Aleuse was 

 still streaming without a definitive bed, a compound network was 

 born which decreased gradually, until only one current, the present 

 Meuse, remained." 



