Experimenting on a raft anchored on the river Elbe, Alfred Nobel tries to make nitroglycerine safer to handle. Finds that the addition of kieselguhr turns nitroglycerine into a dough that can be kneaded, and calls it "dynamite".
There is no river called the Elbe.
( z1 river :polarity - :name ( z2 name :op "Elbe" ) )