There are three versions of this image with different captions.
The actual name is "Sluiskin Falls."
Note the backward 'S' in "Skulken." Otto was writing captions backwards on the glass negatives and sometimes wrote letters without reversing them, so that they are backwards on the postcards.
There are two other images (or image series) numbered 11 or similar:
Reuse of image numbers and different image series make it difficult to know how many images Otto published.