THE WATERS OF THE KARST. 
535 
appreciable effect will tlms be produced upon all tbe tidal 
phenomena of that coast, and, of course, upon the maritime 
geography of Holland. 
A ring dike and canal must then be constructed around 
the landward side of the basin, to exclude and carry off the 
fresh-water streams which now empty into it. One of these, 
the Ijssel, a considerable river, has a course of eighty miles, 
and is, in fact, one of the outlets of the Rhine, though aug¬ 
mented by the waters of several independent tributaries. 
Hiese preparations being made, and perhaps transverse dikes 
erected at convenient points for dividing the gulf into smaller 
portions, the water must be pumped out by machinery, in sub¬ 
stantially the same way as in the case of the Lake of Haarlem. 
Ho safe calculations can be made as to the expenditure of time 
and money required for the execution of this stupendous enter¬ 
prise, but I believe its practicability is not denied by compe¬ 
tent judges, though doubts are entertained as to its financial 
expediency. The geographical results of this improvement 
would be analogous to those of the draining of the Lake of 
Haarlem, but many times multiplied in extent, and its mete¬ 
orological effects, though perhaps not perceptible on the coast, 
could hardly fail to be appreciable in the interior of Holland. 
j 
Waters of the Karst. 
The singular structure of the Karst, the great limestone 
plateau lying to the north of Trieste, has suggested some en¬ 
gineering operations which might be attended with sensible 
effects upon the geography of the province. I have described 
this table land as, though now bare of forests, and almost of 
vegetation, having once been covered with woods, and as being 
completely honeycombed by caves through which the drain¬ 
age of that region is conducted. Schmidl has spent years in 
studying the subterranean geography and hydrography of this 
singular district, and his discoveries, and those of earlier cave- 
hunters, have led to various proposals of physical improve¬ 
ment of a novel character. Many of the underground water- 
