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distances the differences are very great; since the beginning of the 
Diestien the ground has e.g. sunk 20 meters at Grave, 92 meters at 
Goes, 450 meters at Amsterdam. The countries adjoining on the 
south and the west, Belgium and England, have not taken part in 
this movement. 
So we find a real sinking of the land in the Netherlands, which 
movement has been confined to a comparatively small region. 
What then can be the practical significance of the supposed stability 
during the 200 years preceding the year 1860 in connection with 
the gradual considerable sinking in the latest geological periods? 
Not one single movement of the crust of the earth takes place unin¬ 
terruptedly in the same direction without intervals of rest or of 
movement in the opposite direction. Nor does it here. At least since 
pliocene times the ground has continually sunk, but no doubt this 
movement has been interrupted by periods of rest or slight opposed 
movement, which can be really proved, as was stated above. 
But these are only slight sinuosities in a continuous line, whose 
general direction is downward. We cannot assume on geological 
grounds, that a movement, which has proceeded regularly in the 
same direction during a long series of centuries, however irregular 
it may be if only a short portion of time is considered, should have 
ceased just now, because we have not succeeded in demonstrating 
it by measurement during the last two centuries. No, we must much 
sooner assume that the two centuries before I860 present one of 
the numerous small inflections in the line of movement, which on 
the whole runs downward. The rest will certainly be of short 
duration, probably it has already been replaced by a descending 
movement, and geologically speaking we may say in spite of the rest 
during the 200 years preceding the year 1860 observed at Amster¬ 
dam : the ground of the Netherlands has constantly sunk at least 
since pliocene times, and is still in the same long period of subsidence. 
The Hague, June 11th 1909. G. A. F. Molkngkaaff. 
Note on the sinking of the level of the ground of the 
Netherlands . By J. M. van Bemmelen. 
The depths at which the old layers of peat in the quaternary period 
of the strata of the earth are found, render the assumption o * 
lowering of our soil necessary, which is not unimportant. Dr. 0 
has derived from several borings that the sinking in that time 
at least amounted to 18 meters, for at this depth the layer of 
has been found, though originally it has lain at the surface, an 
