Sentence: The stoppage was not so great, therefore, as altogether to arrest the progress of the stream but this sudden obstacle created an accumulation of water behind it, which went on increasing for nearly an hour, till, becoming too powerful to be longer resisted, the enormous dam began to yield, and was swept off at once, and hurled onwards like a floating island.
Combination: a floating island (root: island, modifier: float)
Property: unstable
Property type: emergent